VCO Banda Larga Integrado para Receptor a Cinco Portas

This work presents an wideband ring VCO for cognitive radio five-port based receivers. A three-stage differential topology using transmission gate was adopted in order to maintain wide and linear tuning range and a low phase-noise. Monte-Carlo analysis were performed for phase-shift response of individual stages, which is an important figure of merit in five-port works. It was observed a fairly linear correlation between control voltage and oscillation frequency in the range between 200 MHz and 1800 MHz. The VCO was preliminarily designed for IBM 130nm CMOS technology

Aperfeiçoamento no projeto de um protótipo de misturador-decantador à inversão de fases visando aplicação na indústria do petróleo

In the oil industry the mixture oil/water occurs in the operations of production, transportation and refining, as well as during the use of its derivatives. The amount of water produced associated with the oil varies and can reach values of 90% in volume in the case of mature phase of the production fields. The present work deals with the development of new design of the Mixer Settler based on Phase Inversion (MDIF) in a laboratory scale. We envisage this application in industrial scale so the phases of project, construction and operation are considered. The modifications most significant, in comparison with the original prototype, include the materials of construction and the substitution of the equipment used in the mixing stage of the process. It was tested the viability of substitution of the original system of mechanical mixing by a static mixer. A statistical treatment by means of an experimental design of composed central type was used in order to evaluate the behavior of the main variables of the separation process as function of the efficiency of separation for the new device. This procedure is useful to delimit an optimal region of operation with the equipment. The variables of process considered on the experimental design were: oil concentration in the feeding water (mg/L); Total volumetric flow rate (L/h); Ratio organic/water on volumetric basis (O/A). The separation efficiency is calculated by comparison of the content of oil and greases in the inlet and outlet of the equipment. For determination of TOG (Total Oil and Grease), the method used was based in the absorption of radiation in the infra-red region. The equipment used for these determinations was InfraCal® TOG/TPH Model HATR-T2 of the Wilks Enterprise, Incorporation. It´s important to stand out that this method of measure has being used by PETROBRAS S.A. Results of global efficiency of separation oil/water varied from 75.3 to 97.7% for contaminated waters containing up to 1664,1 mg/L of oil. By means of tests carried out with a real sample of contaminated water supplied by PETROBRAS we have got an effluent specified in terms of the legal standards required for discharging. Thus, the new design of equipment constitutes a real alternative for the conventional systems of treatment of produced water in the oil industry

Estudo de manejo de águas pluviais urbanas na cidade Natal-Rio Grande do Norte

Urban stormwater can be considered as potential water resources as well as problems for the proper functioning of the manifold activities of the city, resulting from inappropriate use and occupation of the soil, usually due to poor planning of the occupation of the development areas, with little care for the environmental aspects of the drainage of surface runoff. As a basic premise, we must seek mechanisms to preserve the natural flow in all stages of development of an urban area, preserving the soil infiltration capacity in the scale of the urban area, comprising the mechanisms of natural drainage, and noting preserving natural areas of dynamic water courses, both in the main channel and in the secondary. They are challenges for a sustainable urban development in a harmonious coexistence of modern developmental, which are consistent with the authoritative economic environmental and social quality. Integrated studies involving the quantity and quality of rainwater are absolutely necessary to achieve understanding and obtaining appropriate technologies, involving both aspects of the drainage problems and aspects of use of water when subjected to an adequate management of surface runoff , for example, the accumulation of these reservoirs in detention with the possibility of use for other purposes. The purpose of this study aims to develop a computer model, adjusted to prevailing conditions of an experimental urban watershed in order to enable the implementation of management practices for water resources, hydrological simulations of quantity and, in a preliminary way, the quality of stormwater that flow to a pond located at the downstream end of the basin. To this end, we used in parallel with the distributed model SWMM data raised the basin with the highest possible resolution to allow the simulation of diffuse loads, heterogeneous characteristics of the basin both in terms of hydrological and hydraulic parameters on the use and occupation soil. The parallel work should improve the degree of understanding of the phenomena simulated in the basin as well as the activity of the calibration models, and this is supported by monitoring data acquired during the duration of the project MAPLU (Urban Stormwater Management) belonging to the network PROSAB (Research Program in Basic Sanitation) in the years 2006 to 2008

Mecanismos de controle do trabalho escolar em propostas de escrita narrativa em livros didáticos de português (1974-2009)

This essay aims at investigating the writing proposals of Portuguese textbooks (LDP Livros Didáticos de Português) for Middle School (EF Ensino Fundamental), from 6th to 9th grade, from the 70s to 2009. It aims to check, though the discourse reported in the Portuguese Textbook, the control directed to the practice of the teacher and the student to do in the teaching situations. Theoretically, we search for contributions that come from the Discourse Analysis of French filiation, so we can analyze the ideological constructions present in the discourse of the ―LDP‖ more specific lly the control directed to the te cher nd student the users of the book, in writing activities. It started from a corpus of 63 textbooks whereof the following steps were performed: a) mapping of the writing proposals contemplated in the ―LDP‖ of high school; b cutting in the selection of propos l ccording to the rese rch go ls intended (writing proposals of narrative texts). After mapping the writing proposals presented in the ―LDP‖ bout the criteri mentioned bove we re d the writing propos ls to ch rt the quantity of proposals of textual writing productions in each textbook (which usually follows a pattern : 12 chapters and, at the end, the writing proposal. Nevertheless, some books present 2 (two) or more writing proposals at the end of each chapter). We did a cutting in the corpus initi lly constituted 63 ―LDP‖ nd we selected 12 writing proposals of narrative texts presented in the ―LDPs‖ to present wh t we intend to n lyze. Then, we separated these proposals into two groups: 1) activities which present ―instruction guide‖ to be followed by the student; 2) writing activities that allow the student write with no need to follow a text pattern, i.e., which encourage authorship. By means of analyses, it was possible to demonstrate that, in the Basic School, generally, the writing practices concentrate, primarily, on copying activities, reproduction, rewriting and, in more advanced levels, in activities that which start from preset models, asking the students to produce text with similar themes, following the suggested structure. It is about ideals that are supposed to be followed and imitated by the students, depriving them to assume their authorship. In order to insert the student in the world of writing it s necess ry to go beyond the model of c nonic l texts pr ctice th t puts the students f r from the possibility to be ― uthors‖. In contr st to this tendency, we face, nowadays, proposals that prioritize the authorship, the creation of a style

Eensino de língua portuguesa: da formação do professor à sala de aula

La reflexión crítica sobre la escuela y los quehaceres docentes ha favorecido la producción y la sistematización de nuevos saberes basados en fundamentos científicos, principalmente sobre las prácticas pedagógicas. En la enseñanza de Lengua Portuguesa, las investigaciones buscan comprender lo qué y cómo se enseña y se aprende durante la escolarización. En esa perspectiva, realizamos un estudio sobre la formación del profesor de Lengua Portuguesa y sus implicaciones en la clase, buscando observar la actuación de los alumnos-maestros en el contexto escolar, durante la realización de las Prácticas. Para tanto, elegimos como objetivo general, investigar cómo la carrera de Filología de la UFRN/CERES/Campus de Currais Novos promovía la formación de futuros profesores para atender a las expectativas de las políticas públicas para la enseñanza de Lengua Materna. Como referencial teórico, estudiamos los PCN, el proyecto político pedagógico de la carrera y autores del área de enseñanza de Lengua Portuguesa y de Educación, entre ellos, Geraldi (1996), Travaglia (1996, 2003), Antunes (2003, 2007, 2009 y 2010), Lomas (2003), Figueiredo (2005), Marcuschi (2001, 2008), Oliveira (2010), Riolfi et al. (2008), Possenti (2003), Alarcão (1996, 2001) Imbernón (2011), Pimenta y Lima (2010) y Schön (1993). El estudio está situado en el ámbito de la Lingüística Aplicada y se caracteriza como investigación cualitativa de naturaleza interpretativista, a partir de un abordaje de inspiración etnográfica del ambiente de las Prácticas. En los resultados constatamos que los alumnos-maestros privilegian la enseñanza prescriptiva, fundamentado en una concepción de lengua como sistema, direccionando la enseñanza de la lengua para la dirección contraria al abordaje funcionalista (lengua / uso), distanciándose considerablemente de la propuesta de formar un alumno crítico y agente de transformación. Respecto a la visión de los alumnos-maestros sobre la carrera, fueron listadas algunas cuestiones relevantes, entre ellas, los contenidos que hacen parte de la carrera, la distribución de la carga horaria de los componentes curriculares, la revisión de las ementas, la oferta de asignaturas de inclusión social, la reorganización de las actividades de la práctica en relación al acompañamiento y orientación a los alumnos-maestros y, especialmente, la desarticulación teoría / práctica que fue considerada como responsable por muchas de las dificultades encontradas por los referidos alumnos en la fase de regencia de clase en la enseñanza de Lengua Portuguesa en los niveles de enseñanza fundamental y media. De ese modo, a partir del análisis de estos significados construidos por los alumnos-maestros sobre el proceso de formación en esa carrera de Letras, constatamos la necesidad de una revisión del proyecto de la carrera, pues éste presenta esas fragilidades que necesitan ser analizadas en función de la mejoría de la calidad de la enseñanza de la graduación

O Macrogênero drama Norte-Riograndense: uma análise de gênero e de discurso sob a perspectiva da linguística sistêmico-funcional

The focus of this qualiquantitative research is the phenomenon we are denominating Drama-of-Rio-Grande-do-Norte, which contemplates short verse texts from the oral tradition, sung and presented on stage by women in communities on the south coast of the northeastern Brazilian State, Rio Grande do Norte. This tradition harkens to the medieval romance of the Iberian Peninsula (CASCUDO, 2001; GURGEL, 1999; GALVÃO, 1993; MAGALHÃES, 1973; ROMERO,1977). The objective of this research is to: identify what characterizes the genre Drama of Rio Grande do Norte; situate this genre within a systemization of genres from the oral tradition in Rio Grande do Norte; investigate the interpersonal relationships of power and solidarity through the role of the women in the discourse, how they see themselves and others, pointing out which elements of the world they evaluate and to identify representations of the feminine in the discourse. The theory of Genre and Register of Martin and Rose (2008) and Generic Structure Potential of Hasan (1989, 1996), which has as a base the Systemic Functional Linguistics of Halliday and Matthiessen (2004), Eggins (1994) among others, offers a theoretical framework for the characterization of the genre through the identification of stages and phases configuring its typology the individual schematic structure and its topology its relation to other phenomena in the oral tradition. Other groupings were mapped of the ‗Macrogenre , from the model of Martin and Rose (2008) as a continuum on two axis: between the poles of how the genre circulates orally x in writing, and recited/individually x staged/collectively; as well as mapping the samples with relation to power using the same model, but with the poles of individual voice x collective voice on an axis between increased power and diminished power. Eleven texts described as Narratives and one Anecdote were selected for the analysis of Attitudes, and Negotiations of power. Through the quantification of semantic discursive resources in the discourse systems of Appraisal (MARTIN; WHITE, 2005) and of Negotiation (MARTIN; ROSE, 2007), as well as reflections about humor (EGGINS; SLADE, 1997) we identified the Attitudes and the Negotiations of interpersonal roles. The quantification is based on the theories of Corpus Linguistics (BERBER SARDINHA, 2010), using WordSmith Tools 5.0 (SCOTT, 2010). Our results show that the Drama-of-Rio-Grande-do-Norte is characterized as a Macrogenre in the Community of Oral Stories, in the Family of Street Theatre/Games, composed of five genre types: Narratives, Praise, Complaints, Anecdotes, and Exemplum. The Macrogenre is characterized by its being circulated orally, staged collectively and the texts analyzed configure in differing degrees of power between men and woman. In synthesis we observe that through humor, the Drama-of-Rio-Grande-do-Norte functions to offer a space for women to voice, comment, judge and orient about social conditions in their communities, such as alcoholism, domestic violence, inequalities before the law etc., as well as circulating positive appreciations of rural/coastal culture and judgments about the behavior of members of the speech community, the role of women being to establish and reinforce norms. We anticipate possible benefits of the addition of the genre analyzed in literacy projects in the schools of Rio Grande do Norte

Uma análise teórica da evolução da rotação estelar

In the past 50 years, large efforts have been made toward the understanding of the stellar evolution. In the observational context, large sets of precise measurements of projected rotational velocity were produced, in particular by the Natal and Geneva groups. From these data, it is now possible to establish the behavior of stellar rotation from the turnoff to the red giant branch. In addition, these data have shown the role of tidal effects on stellar rotation in close binary systems. Nevertheless, relatively little attention has been paid to theoretical studies on the evolution of rotation along the HR Diagram, a topic itself directly associated to the evolution of the stars. Basically, there are two reasons for such a fact, (i) spherical symmetry is not assumed, what leads to a substantial increase in the numerical complexity of equations and (ii) non rotating models have been very successful in explaining relevant observational data, including the mass-luminosity relation and chemical abundances. In spite of these facts, it is clear that considerable work remains to be done on the role of rotation in the later stages of the evolution, where clear disagreements arise from confrontations between theoretical predictions and observations. In the present work we study the evolutionary behavior of stellar rotation along the HR Diagram, taking into account constraint conditions issued from recent observational survey of rotational velocity carried out with high precision procedures and new evolutionary codes

Morfologia em alta resolução espacial de estrelas de tipo Mira e R Corenae Borealis

Mira and R Coronae Borealis (R CrB) variable stars are evolved objects surrounded by circumstellar envelopes (CSE) composed of the ejected stellar material. We present a detailed high-spatial resolution morfological study of the CSE of three stars: IRC+10216, the closest and more studied Carbon-Rich Mira; o Ceti, the prototype of the Mira class; and RY Sagitarii (RY Sgr), the brightest R CrB variable of the south hemisphere. JHKL near-infrared adaptive optics images of IRC+10216 with high dynamic range and Vband images with high angular resolution and high depth, collected with the VLT/NACO and VLT/FORS1 instruments, were analyzed. NACO images of o Ceti were also analyzed. Interferometric observations of RY Sgr collected with the VLTI/MIDI instrument allowed us to explore its CSE innermost regions (»20 40 mas). The CSE of IRC+10216 exhibit, in near-infrared, clumps with more complex relative displacements than proposed in previous studies. In V-band, the majority of the non-concentric shells, located in the outer CSE layers, seem to be composed of thinner elongated shells. In a global view, the morphological connection between the shells and the bipolar core of the nebulae, located in the outer layers, together with the clumps, located in the innermost regions, has a difficult interpretation. In the CSE of o Ceti, preliminar results would be indicating the presence of possible clumps. In the innermost regions (.110 UA) of the CSE of RY Sgr, two clouds were detected in different epochs, embedded in a variable gaussian envelope. Based on a rigorous verification, the first cloud was located at »100 R¤ (or »30 AU) from the centre, toward the east-north-east direction (modulo 180o) and the second one was almost at a perpendicular direction, having aproximately 2£ the distance of the first cloud. This study introduces new constraints to the mass-loss history of these kind of variables and to the morphology of their innermost CSE regions

Parâmetros físico-químicos de estrelas nos campos de exoplanetas do satélite corot

A rotação estelar é um dos mais importantes observáveis da evolução estelar. Neste sentido, o satélite CoRoT representa uma oportunidade única de medir os períodos rotacionais para uma amostra de estrelas estatisticamente robusta, oferecendo dados absolutamente necessários para o estudo da rotação e seu papel na evolução estelar. Para conseguir isto, um passo fundamental é a caracterização física e química das estrelas observadas pelo CoRoT, especificamente devido ao fato de que o cálculo de períodos rotacionais confiáveis é um trabalho difícil sem a ajuda dos parâmetros estelares. Desta forma, foi elaborado um importante seguimento observacional das estrelas nos campos do CoRoT do anticentro LRa01 e do centro LRc01, permitindo a correta identificação dos períodos que reflitam a modulação rotacional. Nesta tese de doutorado são apresentados os resultados de tal seguimento. Parâmetros físicos e químicos, tais como temperatura efetiva Teff , gravidade superficial log(g), velocidade de microturbulência Vmic, abundância de ferro [Fe/H], velocidade de rotação projetada Vsin(i), e abundância de lítio A(Li) são apresentados para uma amostra de 116 estrelas dos campos CoRoT. Elas se encontram em diferentes estágios evolutivos, desde a sequência principal (SP) até o ramo das gigantes vermelhas (GV). As observações foram feitas utilizando os espectrógrafos UVES (VLT) e HYDRA (CTIO). Para a derivação de tais parâmetros foram utilizados o programa TurboSpectrum e os modelos de atmosfera de MARCS. Paralelamente, velocidades rotacionais Vsin(i) foram obtidas a partir do ajuste dos perfis observados e sintéticos das linhas de ferro e por meio de uma calibração de função de correlação cruzada (CCF). Períodos rotacionais Prot para 77 estrelas da amostra foram obtidos a partir das curvas de luz do satélite CoRoT. Extensas tabelas destes parâmetros e seus respectivos erros são apresentadas. Foram encontradas diferenças nas distribuições de Teff , [Fe/H] e estágios evolutivos entre os diferentes campos do CoRoT, indicando possíveis efeitos de seleção na amostra, assim como a existência de diferentes populações estelares do disco Galáctico. Por outro lado, o comportamento rotacional e as abundâncias de lítio não apresentam diferenças entre estrelas de parâmetros físicos similares, mas que pertencem a diferentes campos do CoRoT. A partir da análise de temperaturas, foi encontrada uma maior extinção por avermelhamento para estrelas do CoRoT localizadas no campo LRc01, assim como um gradiente deste valor em função da distância. Os resultados mostram que as abundâncias de lítio, as velocidades de rotação e os períodos rotacionais apresentam o mesmo comportamento descrito na literatura. Por outro lado, é apresentada pela primeira vez a relação que existe entre o lítio e o período de rotação em diferentes estágios evolutivos, mostrando, tal como era esperado, que ambas as grandezas possuem uma anticorrelação. Também é apresentada a evolução simultânea da rotação e do lítio, e foram calculadas relações que permitem obter valores médios de A(Li) como função da temperatura efetiva e do período rotacional. Os dados apresentados nesta tese de doutorado representam um importante ponto de partida para serem utilizados como uma amostra de calibração para diferentes programas no contexto da missão do satélite CoRoT, uma vez que a lista de estrelas aqui analisadas são parte das mais brilhantes que compõem o campo Exo do CoRoT

Rotação diferencial em estrelas do tipo solar

Stellar differential rotation is an important key to understand hydromagnetic stellar dynamos, instabilities, and transport processes in stellar interiors as well as for a better treatment of tides in close binary and star-planet systems. The space-borne high-precision photometry with MOST, CoRoT, and Kepler has provided large and homogeneous datasets. This allows, for the first time, the study of differential rotation statistically robust samples covering almost all stages of stellar evolution. In this sense, we introduce a method to measure a lower limit to the amplitude of surface differential rotation from high-precision evenly sampled photometric time series such as those obtained by space-borne telescopes. It is designed for application to main-sequence late-type stars whose optical flux modulation is dominated by starspots. An autocorrelation of the time series is used to select stars that allow an accurate determination of spot rotation periods. A simple two-spot model is applied together with a Bayesian Information Criterion to preliminarily select intervals of the time series showing evidence of differential rotation with starspots of almost constant area. Finally, the significance of the differential rotation detection and a measurement of its amplitude and uncertainty are obtained by an a posteriori Bayesian analysis based on a Monte Carlo Markov Chain (hereafter MCMC) approach. We apply our method to the Sun and eight other stars for which previous spot modelling has been performed to compare our results with previous ones. The selected stars are of spectral type F, G and K. Among the main results of this work, We find that autocorrelation is a simple method for selecting stars with a coherent rotational signal that is a prerequisite to a successful measurement of differential rotation through spot modelling. For a proper MCMC analysis, it is necessary to take into account the strong correlations among different parameters that exists in spot modelling. For the planethosting star Kepler-30, we derive a lower limit to the relative amplitude of the differential rotation. We confirm that the Sun as a star in the optical passband is not suitable for a measurement of the differential rotation owing to the rapid evolution of its photospheric active regions. In general, our method performs well in comparison with more sophisticated procedures used until now in the study of stellar differential rotation

Aglomerado estelar M67: processos de diluição e a evolução do Momentum Angular

Galactic stellar clusters have a great variety of physical properties that make valuable probes of stellar and galactic chemical evolution. Current studies show a discrepancy between the standard evolutionary models and observations, mainly considering the level of mixing and convective dilution of light elements, as well as to the evolution of the angular momentum. In order to better settle some of these properties, we present a detailed spectroscopic analysis of 28 evolved stars, from the turn-off to the RGB, belonging to the stellar open cluster M67. The observations were performed using UVES+FLAMES at VLT/UT2. We determined stellar parameters and metallicity from LTE analysis of Fe I and Fe II lines between 420 1100 nm. The Li abundance was obtained using the line at 6707.78 ˚A, for the whole sample of stars. The Li abundances of evolved stars of M67 present a gradual decreasing when decreasing the effective temperature. The Li dilution factor for giant stars of M67 with Teff ∼ 4350K is at least 2300 times greater than that predicted by standard theory for single field giant stars. The Li abundance as a function of rotation exhibits a good correlation for evolved stars of M67, with a much smaller dispersion than the field evolved stars. The mass and the age seem to be some of the parameters that influence this connection. We discovered a Li-rich subgiant star in M67 (S1242). It is member of a spectroscopic binary system with a high eccentricity. Its Li abundance is 2.7, the highest Li content ever measured for an evolved star in M67. Two possibilities could explain this anomalous Li content: (i) preservation of the Li at the post turn off stage due to tidal effects, or (ii) an efficient dredge-up of Li, hidden below the convective zone by atomic diffusion occurring in the post turn off stage. We also study the evolution of the angular momentum for the evolved stars in M67. The results are in agreement with previous studies dedicated to evolved stars of this cluster, where stars in the same region of the CM-diagram have quite similar rotations, but with values that indicate an extra breaking along the main sequence. Finally, we analize the distributions of the average rotational velocity and of the average Li abundance as a function of age. With relation to the average Li abundances, stars in clusters and field stars present the same type of exponencial decay law t−β. Such decay is observed for ages lesser than 2 Gyr. From this age, is observed that the average Li abundance remain constant, differently of the one observed in the rotation age connection, where the average rotational velocity decreases slowly with age

Avaliação dos efeitos agudos de diferentes niveis de PEP sobre o padrão respiratório e volumes operacionais de pacientes com Parkinson

Objetivo: Determinar os efeitos agudos de diferentes intensidades de pressão expiratória positiva sobre o padrão respiratório e volumes operacionais de pacientes com doença de Parkinson. Métodos: Foram eleitos para o estudo 23 pacientes em estágios II ou III da doença, estando na condição ON , sendo 8 excluídos, e 15 controles saudáveis. Os indivíduos foram submetidos a uma avaliação inicial, constando de dados gerais, avaliação antropométrica, função pulmonar e força muscular respiratória. Após esta etapa inicial, realizou-se a avaliação dos volumes pulmonares com pletismografia optoeletrônica associado a utilização de pressão expiratória positiva (PEP) em três intensidades de pressão positiva, 10 cmH2O, 15 cmH2O e 20 cmH2O em ordem aleatória. Resultados: O grupo Parkinson apresentou valores espirométricos e de força muscular respiratória significativamente menores que o grupo controle (p<0.01). Houve diferença nos valores de volume corrente (Vt) do grupo Parkinson em relação ao grupo controle na respiração tranqüila (p<0.001) e aumento no Vt do grupo Parkinson com uso das três intensidades de PEP (p<0.001), sem diferenças estatisticamente significativas entre as intensidades e com diferença na distribuição compartimental do Vt entre os grupos (p<0.001). O fluxo inspiratório médio e o volume minuto do grupo Parkinson foram menores em relação ao grupo controle na respiração tranqüila (p<0.001) e aumentaram com o uso das três intensidades de PEP (p<0.001), sem diferenças estatisticamente significativas entre as intensidades. Houve diferença na variação dos volumes operacionais entre os grupos em todas as intensidades de PEP (p < 0.001). O volume pulmonar expiratório final não aumentou no grupo Parkinson com uso de PEP. O volume pulmonar inspiratório final aumentou no grupo Parkinson em todas intensidades de PEP (p < 0.001), não havendo diferenças entre as intensidades. Conclusão: Os pacientes com doença de Parkinson apresentam alterações em diferentes componentes do padrão respiratório e a terapia com PEP determina modificações clinicamente importantes nos volumes pulmonares, considerando a intensidade de 10 cmH2O suficientes para este objetivo terapêutico

Sintomatologia depressiva e concentrações do cortisol em idosos residentes na comunidade: um estudo transversal

Introdução: Vem sendo crescente o número de pesquisas que buscam o entendimento das relações entre os desfechos adversos à saúde e as concentrações do cortisol salivar, o qual é um marcador de estresse biológico. O cortisol parece seguir dois estágios de resposta: em situações de baixo/moderado estresse ocorre ativação do eixo Hipotálamo-Pituitária-Adrenal, aumentando o nível do cortisol, entretanto, quando o estresse persiste, o eixo HPA parece tornar-se hipoativo. A sintomatologia depressiva parece ter relação com as concentrações do cortisol, no entanto, essa relação é controversa na literatura. Objetivo: Analisar a relação entre sintomatologia depressiva e concentrações do cortisol em uma amostra de idosos do Nordeste brasileiro, residentes na comunidade. Métodos: Estudo observacional analítico, de caráter transversal, em uma amostra de 256 idosos (≥ 65 anos), residentes na comunidade. A sintomatologia depressiva foi avaliada pela versão brasileira da Center for Epidemiologic Studies-Depression Scale (≥ 16) e as concentrações do cortisol através da coleta salivar (ao acordar, 30 minutos após acordar, 60 minutos após acordar, às 15 horas e antes de dormir), além de medidas compostas. Como co-variáveis foram avaliadas condições sociodemográficas e de saúde. Para análise das medidas do cortisol entre idosos com e sem presença da sintomatologia depressiva, e entre os sexos, foi realizado o teste t de Student. Para verificar as diferenças entre as medidas do cortisol em cada curva foi utilizada a Análise de Variância (ANOVA) de medidas repetidas, com teste post-hoc de Bonferroni. Resultados: Houve diferença significativa para a medida de cortisol salivar ao acordar, entre os idosos com presença e ausência da sintomatologia depressiva (p=0,04). Não houve significância em relação ao sexo. Na análise entre as medidas de cada curva, foi observado que nos idosos com sintomatologia depressiva a 1ª medida não teve diferença significativa em relação à 2ª e 3ª medidas. Além disso, não houve diferença significativa da 4ª medida em relação à 5ª, demonstrando um maior nível noturno de cortisol para os idosos com sintomatologia depressiva, sem declínio, com aspecto plano da curva. Conclusão: Parece existir relação entre sintomatologia depressiva e hipocortisolismo. Entretanto, no Brasil, as condições adversas de vida podem levar ao estresse crônico e serem fatores fortes suficientes para sobrepor maiores diferenças que pudessem existir em relação à presença da sintomatologia depressiva

Estágio menopausal e níveis hormonais no desenvolvimento muscular e funcional em mulheres de meia idade: um estudo transversal

Introduction: Hypoestrogenism is the main characteristic of female aging. It promotes significant changes in body composition, both in fat mass as in lean body mass, leading to a decrease in muscle strength and physical performance. Objective: The aim of this study was to test whether menopausal status and hormone levels are associated with muscular strength and physical performance in middle-aged women. Methods: In a cross-sectional study it was collected sociodemographic data, gynecological history, anthropometric and biochemical measures in women aged 40 to 65 years in Parnamirim-RN. The menopause status (pre, peri and post menopause) was determined by menstrual history. All women underwent three dimensions of physical performance assessment: handgrip dynamometry, gait speed and chair stands test - Short Physical Performance Battery (SPPB). Categorical data were presented as absolute and relative frequencies. Quantitative data were showed as mean and standard deviation and the normality of distribution was verified with Kolmogorov-Smirnov (KS) test. Biochemical measures of estradiol and follicle-stimulating hormone (FSH) were transformed to log10. ANOVA with Tukey post-test for comparison of variables between the groups pre, peri and post-menopausal was performed and then multiple linear regression analyzes. Results: Two hundred and seventy eight women aged 50.2 (±5.58) years composed this study, being 50 women in premenopausal status (18%), 122 in perimenopausal (43.9%), and 106 postmenopausal stage (38.1%). The groups were different in age (p=0.001), marital relationship duration (p <0.001), number of pregnancies (p=0.001) and parity (p=0.001). Differences in biochemical measures were observed among the groups: estradiol (p<0.001), FSH (p<0.001), total cholesterol (p=0.001). There were no differences in gait velocity between menopausal status. Values in mean of grip strength decreased by postmenopausal women to perimenopausal and premenopausal ones (24.5 ± 5.1, 25.6 ± 5.4, 26.9 ± 4.9 for post-stage, pre and peri menopausas, respectively, p = 0.02) and the performance of chair stands test was better in premenopausal women compared with that in peri and postmenopausal status (p = 0.02). In multiple linear regression for muscle strength, the variables that remained were: age, estradiol and somatic symptoms measured by Menopause Rating Scale-MRS (R2=0.15). While for the xiv chair-stands test the predictors were number of births and FSH values (R2=0.04). Conclusion: There is a relationship between the stages of menopause and muscle performance in measures of grip strength and sit-up test and these are influenced by the fall of estrogens levels. Data suggest that the decrease in muscle strength and physical performance already appear in the transition to menopause stage, pointing to the need for more research in this area and appropriate preventive interventions

Carcinoma epidermóide de língua :correlação clínica, histológica e imuno-histoquímica

Oral squamous cell carcinoma is the most common malignant neoplasm in oral cavity. Several studies have been carried out to establish biologic behaviour criteria of this neoplasm. Thus, the purpose of this experiment was to performe a clinic, morphologic and immunohistochemical analysis, by the expression of cytokeratins 7, 10, 13, 14, 16 and 19 in 30 cases of tongue squamous cell carcinoma from the files of Dr. Luiz Antônio Hospital (Natal-RN). It was verifeid of the immunoexpression the correlation clinic estadiament and histologic gradation system proposed by Bryne (1998), in order to investigate the use of these intermediate filaments as an indicator of tumour progression. Data was collected from the patients file and it was observed that information regarding sex, age and race was resemble to the literature. Data obtained from disease evolution, clinic estadiament, metastasis and expression of cytokeratins 7, 10, 13, 14, 16 and 19 was submited to statistical analysis (Test K2), which showed that only the histologic gradation didn t demonstrated significant correlation to the clinic variables. The expression the cytokeratins presented variation in the analysed tumours. CK 10 expression showed significant correlation to metastasis, and the presence of CK 16 was related to disease evolution (obit/remission) and also with the T3 and T4 of TNM. These results evidenced that metastasis and TNM showed a good efficacy as a prognostic indicator. The histologic gradation proposed by Bryne (1998) didn t reflect the biologic behaviour of the studied tongue squamous cell carcinoma, and the analysis of some intermediate filaments of cytokeratins seems to reflect the biologic behaviour and agressivity of some oral squamous cell carcinoma