On nonlinear dynamics behavior and control of a new model of a magnetically levitated vibrating system, excited by an unbalanced DC motor of limited power supply

We analyze new results on a magnetically levitated body (a block including a magnet whose bottom pole is set in such a way as to repel the upper pole of a magnetic base) excited by a non-ideal energy source (an unbalanced electric motor of limited power supply). These new results are related to the jump phenomena and increase of power required of such sources near resonance are manifestations of a non-ideal system and they are referred as the Sommerfeld effect, which emulates an energy sink. In this work, we also discuss control strategies to be applied to this system, in resonance conditions, in order to decrease its vibration amplitude and avoiding this apparent energy sink.

Blended Online POPBL: uma Abordagem Blended Learning para uma Aprendizagem Baseada em Problemas e Organizada em Projetos

Pós-graduação em Educação - FCT

Teoria dos Jogos aplicada à inteligência competitiva organizacional no âmbito da Ciência da Informação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A língua portuguesa no 5º ano do ensino fundamental: repertórios de ensino no contexto da Prova Brasil/ SAEB

Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

Ações educativas sobre prevenção de acidentes infantis com professoras de educação infantil

Pós-graduação em Educação - FFC

A literatura no Ensino Fundamental - anos iniciais: entre o prazer emancipatório e o escolar pragmático

The Children's Literature is an invaluable tool for human formation, ethics, aesthetics and politics, as well as serves as an instrument for the formation of interdiscourse and transforms teaching procedures of text written production. Then, the investigation of how the literature is being worked in school. Therefore, in this work, constitutes the general objective, to investigate how the teaching of Children's Literature is organized in the early years of elementary school and if that organization promotes the development of literary literacy of the student, and language skills written and the reader behavior, making it critical on several topics. The question that served as a north to the research was the following one: is Teaching Children's Literature, in the early years of elementary school, organized to develop the literary literacy while acting as a catalyst tool for learning to read and write? Have been established the following objectives: a) describe how the teaching of children's literature is organized (teaching routine) in the 1st, 2nd, 3rd, 4th and 5th years of elementary school ; b) identify the literary genres that have worked in each school year, describe how they are worked out, analyze whether this work is related to the teaching of writing and the nature of that relation ship; c) verify if the Children's Literature teaching procedure seeks ways to articulate literary activities with the establishment of the interdiscourse as content for writing the textual production. The methodology that was included was the field research, from a qualitative interpretation approach and it had as direct data source the natural environment in which it was developed the teaching of Children's Literature. The work presents data results analyzed according to the concepts of Aesthetics of Reception (Iser, 1977; Jauss, 1977), and the functions of Literature, according to Candido (2000), Yasuda (2004), among others. From the results were extracted

Discourse and Cooperative Learning in the Math Classroom

In this action research study of my 6th grade math classroom I investigated the effects of increased student discourse and cooperative learning on the students’ ability to explain and understand math concepts and problem solving, as well as its effects on their use of vocabulary and written explanations. I also investigated how it affected students’ attitudes. I discovered that increased student discourse and cooperative learning resulted in positive changes in students’ attitudes about their ability to explain and understand math, as well as their actual ability to explain and understand math concepts. Evidence in regard to use of vocabulary and written explanations generally showed little change, but this may have been related to insufficient data. As a result of this research, I plan to continue to use cooperative learning groups and increased student discourse as a teaching practice in all of my math classes. I also plan to include training on cooperative learning strategies as well as more emphasis on vocabulary and writing in my math classroom.

Cooperative Learning in Relation to Problem Solving in the Mathematics Classroom

In this action research study of my classroom of 5th grade mathematics, I investigated cooperative learning and how it is related to problem solving as well as written and oral communication. I discovered that cooperative learning has a positive impact on students’ abilities in problem solving and their overall impression of mathematics and group work. I also found that my students’ communication skills improved in oral explanations of their work. As a result of this research I plan to continue my implementation of cooperative learning in my classroom as a general method of teaching. I also plan to continue to use cooperative learning in working with my students to increase their achievement in problem solving and communication of mathematics.

Predicting Problematic Approach Behavior Toward Politicians: Exploring the Potential Contributions of Control Theory

The potential merits of Carver and Scheier's (1981) control theory in the prediction of targeted violence are reviewed and several novel indicators of risk that are consistent with this theory are suggested for study. It was hypothesized that: (a) similarity between inappropriate contact with politicians and extremist group literature and writings; (b) the temporal proximity to violent or otherwise criminal actions and notable anniversaries of such groups; (c) detailed specification of a plan to engage in problematic approach behavior, and; (d) self-focus, will be significant predictors of problematic approach behavior. A sample of 506 individuals who engaged in threatening or otherwise inappropriate contact toward members of the United States Congress was drawn from the case files of the United States Capitol Police. Results of the present research indicated that detailed specification of a plan to engage in problematic approach behavior was strongly predictive of actually engaging in problematic approach. Furthermore, high self-focus was significantly related to problematic approach between-persons, although within-person, higher-than-average self-focus showed no such relation. Neither temporal proximity to notable acts of extremist violence nor similarity to known extremist group writings was found to be associated with problematic approach in this sample.

A literatura no Ensino Fundamental - anos iniciais: entre o prazer emancipatório e o escolar pragmático

The Children's Literature is an invaluable tool for human formation, ethics, aesthetics and politics, as well as serves as an instrument for the formation of interdiscourse and transforms teaching procedures of text written production. Then, the investigation of how the literature is being worked in school. Therefore, in this work, constitutes the general objective, to investigate how the teaching of Children's Literature is organized in the early years of elementary school and if that organization promotes the development of literary literacy of the student, and language skills written and the reader behavior, making it critical on several topics. The question that served as a north to the research was the following one: is Teaching Children's Literature, in the early years of elementary school, organized to develop the literary literacy while acting as a catalyst tool for learning to read and write? Have been established the following objectives: a) describe how the teaching of children's literature is organized (teaching routine) in the 1st, 2nd, 3rd, 4th and 5th years of elementary school ; b) identify the literary genres that have worked in each school year, describe how they are worked out, analyze whether this work is related to the teaching of writing and the nature of that relation ship; c) verify if the Children's Literature teaching procedure seeks ways to articulate literary activities with the establishment of the interdiscourse as content for writing the textual production. The methodology that was included was the field research, from a qualitative interpretation approach and it had as direct data source the natural environment in which it was developed the teaching of Children's Literature. The work presents data results analyzed according to the concepts of Aesthetics of Reception (Iser, 1977; Jauss, 1977), and the functions of Literature, according to Candido (2000), Yasuda (2004), among others. From the results were extracted

Ontogeny of manipulative behavior and nut-cracking in young tufted capuchin monkeys (Cebus apella): a Perception-action perspective

How do capuchin monkeys learn to use stones to crack open nuts? Perception-action theory posits that individuals explore producing varying spatial and force relations among objects and surfaces, thereby learning about affordances of such relations and how to produce them. Such learning supports the discovery of tool use. We present longitudinal developmental data from semifree-ranging tufted capuchin monkeys (Cebus apella) to evaluate predictions arising from Perception-action theory linking manipulative development and the onset of tool-using. Percussive actions bringing an object into contact with a surface appeared within the first year of life. Most infants readily struck nuts and other objects against stones or other surfaces from 6 months of age, but percussive actions alone were not sufficient to produce nut-cracking sequences. Placing the nut on the anvil surface and then releasing it, so that it could be struck with a stone, was the last element necessary for nut-cracking to appear in capuchins. Young chimpanzees may face a different challenge in learning to crack nuts: they readily place objects on surfaces and release them, but rarely vigorously strike objects against surfaces or other objects. Thus the challenges facing the two species in developing the same behavior (nut-cracking using a stone hammer and an anvil) may be quite different. Capuchins must inhibit a strong bias to hold nuts so that they can release them; chimpanzees must generate a percussive action rather than a gentle placing action. Generating the right actions may be as challenging as achieving the right sequence of actions in both species. Our analysis suggests a new direction for studies of social influence on young primates learning sequences of actions involving manipulation of objects in relation to surfaces.

Variations in Structure Explain the Viscometric Behavior of AOT Microemulsions at Low Water/AOT Molar Ratios

The viscosity of AOT/water/decane water-in-oil microemulsions exhibits a well-known maximum as a function of water/AOT molar ratio, which is usually attributed to increased attractions among nearly spherical droplets. The maximum can be removed by adding salt or by changing the oil to CCl4. Systematic small-angle X-ray scattering (SAXS) measurements have been used to monitor the structure of the microemulsion droplets in the composition regime where the maximum appears. On increasing the droplet concentration, the scattering intensity is found to scale with the inverse of the wavevector, a behavior which is consistent with cylindrical structures. The inverse wavevector scaling is not observed when the molar ratio is changed, moving the system away from the value corresponding to the viscosity maximum. It is also not present in the scattering from systems containing enough added salt to essentially eliminate the viscosity maximum. An asymptotic analysis of the SAXS data, complemented by some quantitative modeling, is consistent with cylindrical growth of droplets as their concentration is increased. Such elongated structures are familiar from related AOT systems in which the sodium counterion has been exchanged for a divalent one. However, the results of this study suggest that the formation of non-spherical aggregates at low molar ratios is an intrinsic property of AOT.

Word sense disambiguation via high order of learning in complex networks

Complex networks have been employed to model many real systems and as a modeling tool in a myriad of applications. In this paper, we use the framework of complex networks to the problem of supervised classification in the word disambiguation task, which consists in deriving a function from the supervised (or labeled) training data of ambiguous words. Traditional supervised data classification takes into account only topological or physical features of the input data. On the other hand, the human (animal) brain performs both low- and high-level orders of learning and it has facility to identify patterns according to the semantic meaning of the input data. In this paper, we apply a hybrid technique which encompasses both types of learning in the field of word sense disambiguation and show that the high-level order of learning can really improve the accuracy rate of the model. This evidence serves to demonstrate that the internal structures formed by the words do present patterns that, generally, cannot be correctly unveiled by only traditional techniques. Finally, we exhibit the behavior of the model for different weights of the low- and high-level classifiers by plotting decision boundaries. This study helps one to better understand the effectiveness of the model. Copyright (C) EPLA, 2012

Hypoactivity of the central dopaminergic system and autistic-like behavior induced by a single early prenatal exposure to lipopolysaccharide

The aim of the present study was to evaluate the behavioral patterns associated with autism and the prevalence of these behaviors in males and females, to verify whether our model of lipopolysaccharide (LPS) administration represents an experimental model of autism. For this, we prenatally exposed Wistar rats to LPS (100 mu g/kg, intraperitoneally, on gestational day 9.5), which mimics infection by gram-negative bacteria. Furthermore, because the exact mechanisms by which autism develops are still unknown, we investigated the neurological mechanisms that might underlie the behavioral alterations that were observed. Because we previously had demonstrated that prenatal LPS decreases striatal dopamine (DA) and metabolite levels, the striatal dopaminergic system (tyrosine hydroxylase [TH] and DA receptors D1a and D2) and glial cells (astrocytes and microglia) were analyzed by using immunohistochemistry, immunoblotting, and real-time PCR. Our results show that prenatal LPS exposure impaired communication (ultrasonic vocalizations) in male pups and learning and memory (T-maze spontaneous alternation) in male adults, as well as inducing repetitive/restricted behavior, but did not change social interactions in either infancy (play behavior) or adulthood in females. Moreover, although the expression of DA receptors was unchanged, the experimental animals exhibited reduced striatal TH levels, indicating that reduced DA synthesis impaired the striatal dopaminergic system. The expression of glial cell markers was not increased, which suggests that prenatal LPS did not induce permanent neuroinflammation in the striatum. Together with our previous finding of social impairments in males, the present findings demonstrate that prenatal LPS induced autism-like effects and also a hypoactivation of the dopaminergic system. (c) 2012 Wiley Periodicals, Inc.

The endocannabinoid and endovanilloid systems interact in the rat prelimbic medial prefrontal cortex to control anxiety-like behavior

Cannabinoid receptor 1 (CB1) agonists usually induce dose-dependent biphasic effects on anxiety-related responses. Low doses induce anxiolytic-like effects, whereas high doses are ineffective or anxiogenic, probably due to activation of Transient Receptor Potential Vanilloid Type 1 (TRPV1) channels. In this study we have investigated this hypothesis by verifying the effects of the CB1/TRPV1 agonist ACEA injected into the prelimbic medial prefrontal cortex (PL) and the participation of endocannabinoids in the anxiolytic-like responses induced by TRPV1 antagonism, using the elevated plus-maze (EPM) and the Vogel conflict test (VCT). Moreover, we verified the expression of these receptors in the PL by double labeling immunofluorescence. ACEA induced anxiolytic-like effect in the intermediate dose, which was attenuated by previous injection of AM251, a CB1 receptor antagonist. The higher and ineffective ACEA dose caused anxiogenic- and anxiolytic-like effects, when injected after AM251 or the TRPV1 antagonist 6-iodonordihydrocapsaicin (6-I-CPS), respectively. Higher dose of 6-I-CPS induced anxiolytic-like effects both in the EPM and the VCT, which were prevented by previous administration of AM251. In addition, immunofluorescence showed that CB1 and TRPV1 receptors are closely located in the PL These results indicate that the endocannabinoid and endovanilloid systems interact in the PL to control anxiety-like behavior. (C) 2012 Elsevier Ltd. All rights reserved.