Biodistribuição do pertecnetato de sódio (Na99mTcO4) em ratos submetidos à ressecção extensa de intestino delgado

Massive resection of the small intestine results in short bowel syndrome with anti-absorptive effect and repercussions on the metabolism. Morphologic and functional evaluation may be necessary in order to control wrapped organs. Scintigraphy an examination with little invading and no biologic damage can be used. The purpose were to assess the biodistribution of sodium pertecnetate in organs of rats subjected to massive resection of the small intestine, the intestinal adaptation of the remnant intestinal mucosa and weight curve evaluation in the postoperative period. Twenty-one Wistar rats were randomly allocated into three groups (n = 7). The operated group named short bowel (SB) after anesthetized was subjected to massive resection of the small intestine; the control group (C), and sham group (SHAM). On the 30th postoperative day, 0.l mL of sodium pertechnetate was injected into the venous orbital plexus. After 30 minutes, the rats were killed with an overdose of anesthetic, and fragments of the liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, femur and brain were harvested. The percentage of radioactivity per gram of tissue (%ATI/g) was determined using Gama Counter WizardTM 1470, PerkinElmer to all samples. Biopsies of 3 cm remaining jejunum were removed to histological analyses. Analysis of variance (ANOVA) and the Tukey test for multiple comparisons were used, considering p<0.05 as significant. The study had the participation of some departments and laboratories, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research. The results were no significant differences in %ATI/g of the sodium pertechnetate in the organs of the groups studied (p>0.05). An increase in the weight of the SB rats was observed after the second postoperative week. The jejunal mucosal thickness of the SB rats was significantly greater than that of C and sham rats (p<0.05. The biodistribution of sodium pertechnetate was not affected by massive intestinal resection in rats. An adaptive response by the intestinal mucosa probably contributed to the reversion of weight loss and the biodistribution of sodium pertechnetate was not affected by the surgery

Influência da hereditariedade nas capacidades motoras, na aptidão física e antropometria

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Ecologia trófica de anfíbios anuros: relações filogenéticas em diferentes escalas

Understand the origin, maintenance and the mechanisms that operate in the current biodiversity is the major goal of ecology. Species ecology can be influenced by different factors at different scales. There are three approaches about the ecological differences between species: the first brings that differences result from current processes on niche characteristics (e.g. diet, time, space); the second that species differences are explained by random patterns of speciation, extinction and dispersion, the third that historical events explain the formation and composition of species in communities. This study aims to evaluate the influence of phylogenetic relationships in determining ecological characteristics in amphibians (globally) and test with that, if ecological differences between species of frogs are the result of ancient pre-existing differences or as result of current interactions. Another objective of this study is to verify if ecological, historical or current characteristics determine the size of species geographical distribution. The diet data for analysis of trophic ecology were collected from published literature. We performed a non-parametric MANOVA to test the existence of phylogenetic effects in diet shifts on frogs history. Thus, it is expected to know the main factors that allow the coexistence of anuran species. We performed a phylogenetic regression to analyze if niche breadth, body size and evolutionary age variables determine the size of the geographical distribution of amphibians in the Amazon. In the present study, new contributions to knowledge of major ecological patterns of anurans are discussed under a phylogenetic perspective

Tornar-se, ser e viver do professorado: entre regularidades e variações identitárias

The main aim of this research has been to analyze the identity patterns of the teacher s staff of fundamental education public schools in the Metropolitan Area of Natal-RN. It sets out from the hypothesis that being a teacher within this context grows out of the regularities of a specific habitus, which, according to Bourdieu, develops into mental schemes of thought and action within a specific social group. This habitus forms the basis on which is built the social representation of being a teacher prevailing in the group, as well as the symbolic differences that typify its identity variations. Three data sources have been fundamental in building up this thesis: (a) formative essays of students graduating from a Higher Teacher s Formation Course, as well as observing some of the public defense of these essays during field work; (b) a questionnaire aimed at classifying economically, socially, and culturally a sample of public teachers of the Natal-RN county; and (c) submitting a sub-sample of this group to the process of Multiple Classification Procedures (MCP). The analysis of data was done according to the multidimensional, non-parametric statistical procedures of both the Category Content Analysis and Enunciation Analysis methods. The results of the analysis took into account an ample set of variables, its associations and implications, the cultural and social profile of the population under scrutiny, their life styles, as well as the strategies they developed in the process of becoming a teacher, and the social representation of being a teacher . We came to the conclusion that the social identity of the teachers corps, or as we prefer to say it being a teacher , is a result of a set of regularities produced by the habitus that gives social shape and meaning to the existence of the group proper. We note the existence of identity variations caused by the variables (a) educational level; and (b) mode of action in fundamental education (if these are the first or last grades where the subjects operate). However, these variations will not break the power of the regularities that give shape, meaning, and social visibility to the group. The social representation of being a teacher points to the tensions, ambiguities, and trends inherent to common sense, as well as to a strong tendency to reassign a new meaning to being a teacher. Our thesis, therefore, is that the identity configuration of the teachers corps under scrutiny is characterized by an integrative synthesis, by-product of a habitus that is superimposed, and at the same time co-exists with different identity variations

Correlação entre medidas paramétricas e não-paramétricas de estabilidade em soja

Foram avaliadas a adaptabilidade e a estabilidade de genótipos de soja (Glycine max L.) segundo a metodologia clássica de Eberhart e Russell e a estabilidade dos mesmos genótipos pela metodologia não-paramétrica de Huhn. Os experimentos foram conduzidos no delineamento em blocos casualizados, com três repetições e com 30 tratamentos (genótipos de soja), durante três anos consecutivos. As parcelas experimentais foram constituídas por quatro linhas de cultivo, espaçadas de 0,50 m e com densidade de 25 plantas por metro linear. Como área útil, foram tomadas as linhas centrais, eliminando-se 0,5 m de cada extremidade. A comparação entre as metodologias foi efetuada considerando-se o caráter produção de grãos. Verificou-se correlação de posição significativa dos postos dos genótipos, entre o desvio da regressão e as duas medidas não-paramétricas de estabilidade, porém o mesmo não foi observado entre o coeficiente de regressão e as medidas não-paramétricas (Si(1) e Si(2)). As medidas Si(1) e Si(2) mostraram-se quase que perfeitamente correlacionadas.

Estimativas de parâmetros genéticos para produção de leite e persistência da lactação em vacas Gir, aplicando modelos de regressão aleatória

Com o objetivo de estimar parâmetros genéticos para a produção de leite no dia do controle (PLDC), foram usadas as 2.440 primeiras lactações de vacas da raça Gir leiteira, com partos registrados entre 1990 e 2005. As PLDC foram consideradas em dez classes mensais e analisadas por meio de modelo de regressão aleatória (MRA) utilizando-se como efeitos aleatórios o genético-aditivo, o de ambiente permanente e o residual e, como efeitos fixos, o grupo de contemporâneos (GC), a co-variável idade da vaca ao parto (efeito linear e quadrático) e a curva média de lactação da população. Os efeitos genético-aditivos e de ambiente permanente foram modelados utilizando-se as funções de Wilmink (WIL) e Ali e Schaeffer (AS). As variâncias residuais foram modeladas utilizando-se 1, 4, 6 ou 10 classes. Os grupos de contemporâneos foram definidos como rebanho-ano-estação do controle contendo no mínimo três animais. Os testes indicaram que o modelo com quatro classes de variâncias usando a função paramétrica AS foi o que melhor se ajustou aos dados. As estimativas de herdabilidade variaram de 0,21 a 0,33 para a função AS e de 0,17 a 0,30 para WIL e foram maiores na primeira metade da lactação. As correlações genéticas entre as PLDC foram positivas e elevadas entre os controles adjacentes e diminuiram quando a distância entre os controles aumentou. Para o melhor modelo, foram estimados os valores genéticos para a produção de leite acumulada até os 305 dias e, para períodos parciais da lactação, foram obtidas como médias dos valores genéticos preditos naquele período. Os valores genéticos foram comparados, por meio da correlação de posto, ao valor genético predito para a produção acumulada até os 305 dias, pelo método tradicional. As correlações entre os valores genéticos indicaram que podem ocorrer divergências na classificação dos animais pelos critérios estudados.

Comparações entre os valores genéticos para características de crescimento de bovinos da raça Nelore preditos com modelos de dimensão finita ou infinita

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Funções de covariância para produção de leite no dia do controle em bovinos Gir leiteiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação de robustez, desempenho e aplicação do controlador adaptativo por posicionamento de pólos e estrutura variável

In this work, the variable structure adaptive pole placement controller (VS-APPC) robustness and performance are evaluated and this algorithm is applied in a motor control system. The controller robustness evaluation will be done through simulations, where will be introduced in the system the following adversities: time delay, actuator response boundeds, disturbances, parametric variation and unmodeled dynamics. The VS-APPC will be compared with PI control, pole placement control (PPC) and adaptive pole placement controller (APPC). The VS-APPC will be simulated to track a step and a sine reference. It will be applied in a three-phase induction motor control system to track a sine signal in the stator reference frame. Simulation and experimental results will prove the efficiency and robustness of this control strategy

Metodologia estatística na solução do problema do caixeiro viajante e na avaliação de algoritmos : um estudo aplicado à transgenética computacional

The problems of combinatory optimization have involved a large number of researchers in search of approximative solutions for them, since it is generally accepted that they are unsolvable in polynomial time. Initially, these solutions were focused on heuristics. Currently, metaheuristics are used more for this task, especially those based on evolutionary algorithms. The two main contributions of this work are: the creation of what is called an -Operon- heuristic, for the construction of the information chains necessary for the implementation of transgenetic (evolutionary) algorithms, mainly using statistical methodology - the Cluster Analysis and the Principal Component Analysis; and the utilization of statistical analyses that are adequate for the evaluation of the performance of the algorithms that are developed to solve these problems. The aim of the Operon is to construct good quality dynamic information chains to promote an -intelligent- search in the space of solutions. The Traveling Salesman Problem (TSP) is intended for applications based on a transgenetic algorithmic known as ProtoG. A strategy is also proposed for the renovation of part of the chromosome population indicated by adopting a minimum limit in the coefficient of variation of the adequation function of the individuals, with calculations based on the population. Statistical methodology is used for the evaluation of the performance of four algorithms, as follows: the proposed ProtoG, two memetic algorithms and a Simulated Annealing algorithm. Three performance analyses of these algorithms are proposed. The first is accomplished through the Logistic Regression, based on the probability of finding an optimal solution for a TSP instance by the algorithm being tested. The second is accomplished through Survival Analysis, based on a probability of the time observed for its execution until an optimal solution is achieved. The third is accomplished by means of a non-parametric Analysis of Variance, considering the Percent Error of the Solution (PES) obtained by the percentage in which the solution found exceeds the best solution available in the literature. Six experiments have been conducted applied to sixty-one instances of Euclidean TSP with sizes of up to 1,655 cities. The first two experiments deal with the adjustments of four parameters used in the ProtoG algorithm in an attempt to improve its performance. The last four have been undertaken to evaluate the performance of the ProtoG in comparison to the three algorithms adopted. For these sixty-one instances, it has been concluded on the grounds of statistical tests that there is evidence that the ProtoG performs better than these three algorithms in fifty instances. In addition, for the thirty-six instances considered in the last three trials in which the performance of the algorithms was evaluated through PES, it was observed that the PES average obtained with the ProtoG was less than 1% in almost half of these instances, having reached the greatest average for one instance of 1,173 cities, with an PES average equal to 3.52%. Therefore, the ProtoG can be considered a competitive algorithm for solving the TSP, since it is not rare in the literature find PESs averages greater than 10% to be reported for instances of this size.

Um ambiente computacional para modelagem simbólica de sistemas físicos lineares

Este trabalho propõe um ambiente computacional aplicado ao ensino de sistemas de controle, denominado de ModSym. O software implementa uma interface gráfica para a modelagem de sistemas físicos lineares e mostra, passo a passo, o processamento necessário à obtenção de modelos matemáticos para esses sistemas. Um sistema físico pode ser representado, no software, de três formas diferentes. O sistema pode ser representado por um diagrama gráfico a partir de elementos dos domínios elétrico, mecânico translacional, mecânico rotacional e hidráulico. Pode também ser representado a partir de grafos de ligação ou de diagramas de fluxo de sinal. Uma vez representado o sistema, o ModSym possibilita o cálculo de funções de transferência do sistema na forma simbólica, utilizando a regra de Mason. O software calcula também funções de transferência na forma numérica e funções de sensibilidade paramétrica. O trabalho propõe ainda um algoritmo para obter o diagrama de fluxo de sinal de um sistema físico baseado no seu grafo de ligação. Este algoritmo e a metodologia de análise de sistemas conhecida por Network Method permitiram a utilização da regra de Mason no cálculo de funções de transferência dos sistemas modelados no software

Controlador preditivo generalizado multi-modelo aplicado ao controle de pressão arterial

Postsurgical complication of hypertension may occur in cardiac patients. To decrease the chances of complication it is necessary to reduce elevated blood pressure as soon as possible. Continuous infusion of vasodilator drugs, such as sodium nitroprusside (Nipride), would quickly lower the blood pressure in most patients. However, each patient has a different sensitivity to infusion of Nipride. The parameters and the time delays of the system are initially unknown. Moreover, the parameters of the transfer function associated with a particular patient are time varying. the objective of the study is to develop a procedure for blood pressure control i the presence of uncertainty of parameters and considerable time delays. So, a methodology was developed multi-model, and for each such model a Preditive Controller can be a priori designed. An adaptive mechanism is then needed for deciding which controller should be dominant for a given plant

Identificação em tempo real de modelo dinâmico de robô móvel com acionamento diferencial e zona morta

Several mobile robots show non-linear behavior, mainly due friction phenomena between the mechanical parts of the robot or between the robot and the ground. Linear models are efficient in some cases, but it is necessary take the robot non-linearity in consideration when precise displacement and positioning are desired. In this work a parametric model identification procedure for a mobile robot with differential drive that considers the dead-zone in the robot actuators is proposed. The method consists in dividing the system into Hammerstein systems and then uses the key-term separation principle to present the input-output relations which shows the parameters from both linear and non-linear blocks. The parameters are then simultaneously estimated through a recursive least squares algorithm. The results shows that is possible to identify the dead-zone thresholds together with the linear parameters

Modelagem linear e identificação do modelo dinâmico de um robô móvel com acionamento diferencial

This work presents a modelling and identification method for a wheeled mobile robot, including the actuator dynamics. Instead of the classic modelling approach, where the robot position coordinates (x,y) are utilized as state variables (resulting in a non linear model), the proposed discrete model is based on the travelled distance increment Delta_l. Thus, the resulting model is linear and time invariant and it can be identified through classical methods such as Recursive Least Mean Squares. This approach has a problem: Delta_l can not be directly measured. In this paper, this problem is solved using an estimate of Delta_l based on a second order polynomial approximation. Experimental data were colected and the proposed method was used to identify the model of a real robot

Caracterização de superfícies seletivas de freqüência e de antenas fractais para aplicações em redes sem fio

This work aims to investigate the behavior of fractal elements in planar microstrip structures. In particular, microstrip antennas and frequency selective surfaces (FSSs) had changed its conventional elements to fractal shapes. For microstrip antennas, was used as the radiating element of Minkowski fractal. The feeding method used was microstrip line. Some prototypes were built and the analysis revealed the possibility of miniaturization of structures, besides the multiband behavior, provided by the fractal element. In particular, the Minkowski fractal antenna level 3 was used to exploit the multiband feature, enabling simultaneous operation of two commercial tracks (Wi-Fi and WiMAX) regulated by ANATEL. After, we investigated the effect of switches that have been placed on the at the pre-fractal edges of radiating element. For the FSSs, the fractal used to elements of FSSs was Dürer s pentagon. Some prototypes were built and measured. The results showed a multiband behavior of the structure provided by fractal geometry. Then, a parametric analysis allowed the analysis of the variation of periodicity on the electromagnetic behavior of FSS, and its bandwidth and quality factor. For numerical and experimental characterization of the structures discussed was used, respectively, the commercial software Ansoft DesignerTM and a vector network analyzer, Agilent N5230A model