Efeito do treinamento resistido na função autônomica cardíaca, nos parâmetros bioquímicos e antropométricos de pessoas vivendo com HIV/AIDS

Introduction: The emergence of High Active Antiretroviral Therapy (HAART) increase the life expectancy of the persons living with HIV/AIDS (PLHIV), therefore the prolonged use cause metabolic implications and influences on body fat distribution and increase the cardiovascular diseases prevalence. Aims: Evaluate the effect of resistance training on heart rate variability, biochemical parameters and somatotype on PLHIV. Methods: Participated this study seven sedentary men, with age above 25 years old, living with HIV/AIDS, under HAART use. Were submitted a 16 week intervention with resistance training. Evaluated the heart rate variability, biochemical parameters and somatotype, before, after 8 weeks and 16 weeks, all in paired form. It was found the data normality by Shapiro-Wilk test and conducted the Anova one way combined with Tukey post hoc to samples in each evaluate moment, adopting significance level p<0,05. Also were calculated percentage change deltas. For somatotype was used the somatotype spatial distance (DES), obeying the significance value DES≥1. Results: Was found significance differences only in variable final heart rate delta 60s (p=0,01), however, is not showed changes on heart rate variability, biochemical parameters and somatotype components. Conclusion: 16 weeks of resistance training showed improvement on heart rate recovery after submaximal effort and, despite is not enough to produce significance differences on biochemical parameters and somatotype components, could be realize improvement on average value of fasting glucose and lipid profile, as well as reducing the endomorphic component

Modelo de desdobramento da função qualidade adequado a produção da cerâmica vermelha

A presente dissertação representa uma contribuição na resolução dos problemas que se apresentam no setor das indústrias de cerâmica vermelha, apresentamos um modelo, baseado na estratégia do QFD (Desdobramento da Função Qualidade), na qual associa os requisitos dos consumidores na elaboração dos projetos do produto e dos processos de produção. A qualidade do produto é avaliada tanto no aspecto interno(especificações técnicas) quanto no aspecto externo (qualidades exigidas pelos clientes). A pesquisa mostra, além da realidade que vive o setor das indústrias de cerâmica, a importância e os atributos da qualidade definidos pelos consumidores relativo aos tijolos cerâmicos de vedação. O trabalho também mostra os resultados da aplicação do modelo numa das empresas do setor, através de desdobramentos da qualidade exigida, se estabelece a qualidade planejada, mostra ainda a posição da empresa em relação aos concorrentes em função do desempenho do produto. Procura-se ainda, através de sugestões de melhorias, atacar os problemas das falhas na qual geram o desperdício

Determinação dos parâmetros do controlador preditivo generalizado com função de pesos variante no tempo através de algoritmos genéticos

The predictive control technique has gotten, on the last years, greater number of adepts in reason of the easiness of adjustment of its parameters, of the exceeding of its concepts for multi-input/multi-output (MIMO) systems, of nonlinear models of processes could be linearised around a operating point, so can clearly be used in the controller, and mainly, as being the only methodology that can take into consideration, during the project of the controller, the limitations of the control signals and output of the process. The time varying weighting generalized predictive control (TGPC), studied in this work, is one more an alternative to the several existing predictive controls, characterizing itself as an modification of the generalized predictive control (GPC), where it is used a reference model, calculated in accordance with parameters of project previously established by the designer, and the application of a new function criterion, that when minimized offers the best parameters to the controller. It is used technique of the genetic algorithms to minimize of the function criterion proposed and searches to demonstrate the robustness of the TGPC through the application of performance, stability and robustness criterions. To compare achieves results of the TGPC controller, the GCP and proportional, integral and derivative (PID) controllers are used, where whole the techniques applied to stable, unstable and of non-minimum phase plants. The simulated examples become fulfilled with the use of MATLAB tool. It is verified that, the alterations implemented in TGPC, allow the evidence of the efficiency of this algorithm

Análise de superfícies seletivas de freqüência através do método dos potenciais vetorias de Hertz

This work presents a theoretical and numerical analysis of Frequency Selective Surfaces (FSS) with elements as rectangular patch, thin dipole and crossed dipole mounted on uniaxial anisotropic dielectric substrate layers for orientations of the optical axis along x, y and z directions. The analysis of these structures is accomplished by combination of the Hertz vector potentials method and the Galerkin's technique, in the Fourier transform-domain, using entire¬domain basis functions. This study consists in the use of one more technique for analysis of FSS on anisotropic dielectric substrate. And presents as the main contribution the introduction of one more project parameter to determinate the transmission and reflection characteristics of periodic structures, from the use of anisotropic dielectric with orientations of the crystal optical axis along x, y and z directions. To validate this analysis, the numerical results of this work are compared to those obtained by other authors, for FSS structures on anisotropic and isotropic dielectric substrates. Also are compared experimental results and the numerical correspondent ones for the FSS isotropic case. The technique proposed in this work is accurate and efficient. ln a second moment, curves are presented for the transmission and reflection characteristics of the FSS structures using conducting patch elements mounted on uniaxial anisotropic dielectric substrate layers with optical axis oriented along x, y and z directions. From analysis of these curves, the performance of the considered FSS structures as function of the optical axis orientation is described

Caracterização de escovas de grafite e avaliação do seu desempenho em função da microestrutura

The electric can be converted into thermal, luminous, electromagnetic, and also in mechanical energy. In this context the electric engines plays a fundamental role, specially that they work very below of its nominal capacity, with consequent decrease load density. In industrial environment, these characteristics of work of DC engines had also generated an extreme consumption of coal brushs and attack in the commutator reducing the useful life of the engine and increasing maintenance demand and cost. The general objective of the present work is to study the influence of the granulometry of the coal brush used in DC engines with the resistance to the consumption of the same ones, as well as in the performance presented by the commutator of the engine. Additionally, determining the measurable and not measurable profits when the brush used is adjusted to the application. The brushes had been produced by an industry of the sector and tested in industrial environment to evaluate their performance and consumption. Preliminary results evidence a substantial improvement in the performance of these brushes in function of its microstructure and the application in which it is used

Desgaste de polímeros estruturais de engenharia em contato de deslizamento com cilindro metálico

Present work proposed to map and features the wear mechanisms of structural polymers of engineering derived of the sliding contact with a metallic cylindrical spindle submitted to eccentricity due to fluctuations in it is mass and geometric centers. For this it was projected and makes an experimental apparatus from balancing machine where the cylindrical counterbody was supported in two bearings and the polymeric coupon was situated in a holder with freedom of displacement along counterbody. Thus, the experimental tests were standardized using two position of the two bearings (Fixed or Free) and seven different positions along the counterbody, that permit print different conditions to the stiffness from system. Others parameters as applied normal load, sliding velocity and distance were fixed. In this investigation it was used as coupon two structural polymers of wide quotidian use, PTFE (polytetrafluroethylene) and PEEK (poly-ether-ether-ketone) and the AISI 4140 alloy steel as counterbody. Polymeric materials were characterized by thermal analysis (thermogravimetric, differential scanning calorimetry and dynamic-mechanical), hardness and rays-X diffractometry. While the metallic material was submitted at hardness, mechanical resistance tests and metallographic analysis. During the tribological tests were recorded the heating response with thermometers, yonder overall velocity vibration (VGV) and the acceleration using accelerometers. After tests the wear surface of the coupons were analyzed using a Scanning Electronic Microscopy (SEM) to morphological analysis and spectroscopy EDS to microanalysis. Moreover the roughness of the counterbody was characterized before and after the tribological tests. It was observed that the tribological response of the polymers were different in function of their distinct molecular structure. It were identified the predominant wear mechanisms in each polymer. The VGV of the PTFE was smaller than PEEK, in the condition of minimum stiffness, in function of the higher loss coefficient of that polymer. Wear rate of the PTFE was more of a magnitude order higher than PEEK. With the results was possible developed a correlation between the wear rate and parameter (E/ρ)1/2 (Young modulus, E, density, ρ), proportional at longitudinal elastic wave velocity in the material.

Desenvolvimento de uma desfribadeira para obtenção da fibra da folha do abacaxi

In 1998 the first decorticator was developed in the Textile Engineering Laboratory and patented for the purpose of extracting fibres from pineapple leaves, with the financial help from CNPq and BNB. The objective of the present work was to develop an automatic decorticator different from the first one with a semiautomatic system of decortication with automatic feeding of the leaves and collection of the extracted fibres. The system is started through a command system that passes information to two engines, one for starting the beater cylinder and the other for the feeding of the leaves as well as the extraction of the decorticated fibres automatically. This in turn introduces the leaves between a knife and a beater cylinder with twenty blades (the previous one had only 8 blades). These blades are supported by equidistant flanges with a central transmission axis that would help in increasing the number of beatings of the leaves. In the present system the operator has to place the leaves on the rotating endless feeding belt and collect the extracted leaves that are being carried out through another endless belt. The pulp resulted form the extraction is collected in a tray through a collector. The feeding of the leaves as well as the extraction of the fibres is controlled automatically by varying the velocity of the cylinders. The semi-automatic decorticator basically composed of a chassis made out of iron bars (profile L) with 200cm length, 91 cm of height 68 cm of width. The decorticator weighs around 300Kg. It was observed that the increase in the number of blades from 8 to twenty in the beater cylinder reduced the turbulence inside the decorticator, which helped to improve the removal of the fibres without any problems as well as the quality of the fibres. From the studies carried out, from each leaf 2,8 to 4,5% of fibres can be extracted. This gives around 4 to 5 tons of fibres per hectare, which is more than that of cotton production per hectare. This quantity with no doubt could generate jobs to the people not only on the production of the fibres but also on their application in different areas

Caracterização espacial de reservatórios do semiárido em função da qualidade da água através do uso de componentes principais

A região semiárida sofre escassez hídrica. A fim de regularizar a disponibilidade hídrica nos períodos de estiagem, são construídas barragens. No entanto, a qualidade da água armazenada tem sofrido os efeitos do descarte irregular de resíduos no meio ambiente e das atividades antrópicas exercidas nas bacias hidrográficas. A degradação hídrica pode ser constatada a partir do monitoramento dos parâmetros de qualidade da água. Estes dados podem ser analisados através de métodos estatísticos tais como a Análise de Componentes Principais e a análise de agrupamento, que seleciona indivíduos com características semelhantes. O objetivo deste trabalho é realizar oagrupamento dos reservatórios do Rio Grande do Norte, com base nos parâmetros de qualidade da água, para a identificação de grupos homogêneos de reservatórios em termos de fontes de poluição. Serão objeto desse estudo as bacias Piranhas-Açu, Apodi-Mossoró, Trairí, Potengi e Ceará-Mirim. Os parâmetros mercúrio, chumbo, cromo, fósforo total, nitrogênio total e zinco contribuíram para a formação da primeira componente principal, que pode indicar poluição por metais pesados; sólidos totais, DBO, OD e cobre, para a segunda componente, que pode ser indicativo de poluição por matéria orgânica e atividades antrópicas; e clorofila a , cádmio e níquel, para a terceira componente, que pode indicar eutrofização e poluição por metais pesados. De posse das componentes principais se procedeu o agrupamento dos reservatórios, formando-se quatro grupos distintos. Os grupos 1 e 2 são constituídos por reservatórios da Bacia Piranhas-Açu, que apresentou maiores valores de metais pesados. O grupo 3, constituído por reservatórios das bacias Ceará-Mirim, Potengi e Trairí, apresentou maiores valores de DBO e sólidostotais e o grupo 4 é formado por reservatórios da Bacia Apodi-Mossoró. Nas Bacias do Trarí e Piranhas-Açu deve ser coibido o lançamento desordenado de efluentes e fontes de poluição difusas, e implantado um sistema de coleta de esgoto para minimizar a poluição por matéria orgânica

Investigação histórica na formação de professores de matemática: um estudo centrado no conceito de função

In this study we analyzed the development of a teaching experience, involving students with a bachelor s degree in mathematics from UFRN, based on the history of mathematics and mathematical investigations with the aim of contributing to the improvement of the teaching-learning of mathematics. The historical investigation tasks were planned and applied in the classroom, focusing on functional thought. The results obtained during the experience were described and evaluated based on authors who support the assumption of investigation and history as an alternative to the learning of mathematics. We emphasize that the material of analysis consisted of a work diary, audio recordings, questionnaires with testimony of the students involved, and, in addition, the assessment of the teacher of that subject. With regard to the mathematical content, the study was restricted to the concept of function, forms of representation and notation. It was evident that students showed great improvement with regard to the necessary formalization of the mathematical contents which were focused on, and to the active involvement of the students at different stages of the study. We can affirm that the completed study certainly represents significant contributions to an approach in the teaching-learning of functional thought

O uso da abordagem CTSA para o ensino de energia tendo o desenvolvimento sustentável como eixo temático

In recent decades, humanity has become increasingly concerned with environmental problems. Proofs of this are increasing initiatives in civil society organizations, private institutions and government actions, either local, state or national actions to promote environmental protection. The goal of this research is to contribute to the formation of citizens more aware of their responsibilities to sustainable development issues, simultaneously to their learning of physics in the secondary school. Thus, we have designed a research project that aims to evaluate the effectiveness of the adoption of the concept of sustainable development as a central theme in physics classes in high school. From this goal, we designed, implemented and evaluate lesson plans that aim not only to construct and apply the concept of energy, but also to understand their transformations and conservation law, as well as their processes of production, distribution and consume in the context of physical laws in which it is involved. Then, it was deliberately provided to students, during classes, to read, interpret and produce texts, by this way being able to think and start to have a critical view of the world around him, as well as absorb the energy concept and understand his occurrence in phenomena of nature and in technologies. The approach used for this was that constraining science, technology, society and environment - STSE. This teaching methodology has been applied in the IFRN Ipanguaçu campus, for students of two classes of first year of high school integrated course in agroecology and in technical computing. The survey results show the effectiveness of both methods with respect to the viewpoints of students in relation to the guidelines of sustainable development and the learning of physics content proposed. It is hoped with this dissertation to contribute to the formation of future men and women as citizens environmentally friendly, but also as a source of inspiration for teachers who wish to foster in its students such a critical position about civic education, from their classes

Formas e função do discurso do outro no gênero monográfico

The present work investigates related discourse in rewriting discursive practices, at monographic works specifically at the theoretical foundation section. Focalizing some discursive strategies of voice management (direct and indirect discourse and modalization voice) we detach the introduction way and function of cited discourse. To do so, it were analyzed eighteen monographic works: nine of them final graduation works and other nine specialization works seeing that each works belonging to the same student, in two different stages, in the period from 2003 in graduation conclusion to 2005 in the end of specialization course. The data reveal that the monographic writer/student emphasizes the use of direct discourse in graduation works while in specialization works there was an emphasis at indirect speech. The analysis the way they introduce cited discourse pointed out that writer/student in graduation course such as specialization student make meaningless constructions when they do not use discendi verbs, they demonstrate difficulties inarticulate citing discourse with cited discourse. In what is related to functions of cited discourse we verify that the student/writer, in both stages or levels give emphasis to the function maintain an assertion, indicating that other s discourse serve mainly as a resource of authority just because that this function reveals the absence of a dialog between student writing and cited discourse. In a general way, the forms of other s discourse claim a form of writing that is found starting from a sequence of cited discourse in what student/writer voice in graduation and specialization comes to text surface just few times, but most of the times, the student takes other s words as they were themselves, every time there is an overlap of author/source

Aspectos dinâmicos da água versus álcool e acetona por técnicas de congelamento

Water still represents, on its critical properties and phase transitions, a problem of current scientific interest, as a consequence of the countless open questions and of the inadequacy of the existent theoretical models, mainly related to the different solid and liquid phases that this substance possesses. For example, there are 13 known crystalline forms of water, and also amorphous phases. One of them, the amorphous ice of very high density (VHDA), was just recently observed. Other example is the anomalous behavior in the macroscopic density, which presents a maximum at the temperature of 277 K. In order to experimentally investigate the behavior of one of the liquid-solid phase transitions, the anomaly in its density and also the metastability, we used three different cooling techniques and, as comparison systems, we made use of the solvents: acetone and ethyl alcohol. The first studied cooling system employ a Peltier plate, a device recently developed, which makes use of small cubes made up of semiconductors to change heat among two surfaces; the second system is a commercial refrigerator, similar to the residential ones. Finally, the liquid nitrogen technique, which is used to refrigerate the samples in a container, in two ways: a very fast and other one, almost static. In those three systems, three Beckers of aluminum were used (with a volume of 80 ml, each), containing water, alcohol and acetone. They were closed and maintained at atmospheric pressure. Inside of each Becker were installed three thermocouples, disposed along the vertical axis of the Beckers, one close to the inferior surface, other to the medium level and the last one close the superior surface. A system of data acquisition was built via virtual instrumentation using as a central equipment a Data-Acquisition board. The temperature data were collected by the three thermocouples in the three Beckers, simultaneously, in function of freezing time. We will present the behavior of temperature versus freezing time for the three substances. The results show the characterization of the transitions of the liquid

Propriedades magnéticas de nanopartículas de ferro em substratos antiferromagnéticos

The effect of finite size on the magnetic properties of ferromagnetic particles systems is a recurrent subject. One of the aspects wide investigated is the superparamagnetic limit where the temperature destroys the magnetic order of ferromagnetic small particles. Above the block temperature the thermal value of the magnetic moment of the particle vanishes, due to thermal fluctuations. The value of the blocking temperature diminishes when the size of the particle is reduced, reflecting the reduction of the anisotropy energy barrier between the uniform states along the uniaxial axis. The increasing demand for high density magnetic media has recently attracted great research interest in periodic arrangements of nanometric ferromagnetics particles, approach in the superparamagnetic limit. An interesting conjecture is the possibility of stabilization of the magnetic order of small ferromagnetic particles (F) by interface coupling with antiferromagnetic (AF) substrate. These F/AF systems may also help to elucidate some details of the effect of exchange bias, because the effect of interface roughness and the paper of domain walls, either in the substrate or the particle, are significantly reduced. We investigate the magnetic phases of small ferromagnetic particles on a antiferromagnetic substrate. We use a self-consistent local field method, incorporating the interface field and the dipole interaction between the spins of the ferromagnetic particle. Our results indicate that increasing the area of the interface favors the formation of the uniform state. Howere above a critical height value appears a state non-uniform is formed where the spins of in the particle s free surface are rotated with respect to the interface spins direction. We discuss the impact of the competition between the dipolar and interface field on the magnetic charge, that controls the field of flux leakage of the particle, and on the format of the hysteresis curves. Our results indicate that the liquid magnetic charge is not a monotonically increasing function of the height of the particle. The exchange bias may display anomalous features, induced for the dipolar field of the spins near the F/AF interface

Função de distribuição generalizada aplicada à velocidade de rotação estelar

In the present work we use a Tsallis maximum entropy distribution law to fit the observations of projected rotational velocity measurements of stars in the Pleiades open cluster. This new distribution funtion which generalizes the Ma.xwel1-Boltzmann one is derived from the non-extensivity of the Boltzmann-Gibbs entropy. We also present a oomparison between results from the generalized distribution and the Ma.xwellia.n law, and show that the generalized distribution fits more closely the observational data. In addition, we present a oomparison between the q values of the generalized distribution determined for the V sin i distribution of the main sequence stars (Pleiades) and ones found for the observed distribution of evolved stars (subgiants). We then observe a correlation between the q values and the star evolution stage for a certain range of stel1ar mass

Efeitos de interface em bicamadas magnéticas

We study magnetic interface roughness in F/AF bilayers. Two kinds of roughness were considered. The first one consists of isolated defects that divide the substrate in two regions, each one with an AF sub-lattice. The interface exchange coupling is considered uniform and presents a sudden change in the defects line, favoring Neel wall nucleation. Our results show the interface field dependence of the threshold thickness for the reorientation of the magnetization in the ferromagnetic film. Angular profiles show the relaxation of the magnetization, from Neel wall, at the interface, to reoriented state, at the surface. External magnetic field, perpendicular to the easy axis of the substrate, favors the reoriented state. Depending, of the external magnetic field intensity, parallel to the easy axis of the AF, the magnetization profile at surface can be parallel or perpendicular to the field direction. The second one treats of distributed deffects, periodically. The shape hysteresis curves, exchange bias and coercivity were characterized by interface field intensity and roughness pattern. Our results show that dipolar effects decrease the exchange bias and coercivity