Tecnologia do Polargraph e suas aplica??es em sala de aula

Sendo uma m?quina de baixo custo, de projeto e softwares livres e que funcionam em plataformas de amplo alcance de p?blico, o Polargraph ? um rob? desenhista feito de materiais simples e de f?cil aquisi??o (principalmente via internet), desenvolvida pelo programador, designer e inventor escoc?s Sandy Noble. Sua aplica??o em sala de aula vai desde a explica??o de como funciona o software (todos os conceitos matem?ticos envolvidos) at? os desenhos de fato, feitos a partir de coordenadas cartesianas, o que leva a uma compreens?o imediata de que o movimento preciso de rob?s somente pode ser feito por meio de c?lculos matem?ticos, e que quanto mais precisos os c?lculos e a tecnologia das partes utilizadas, mais precisos cam os movimentos, o que pode levar a diversas nalidades. Evidentemente h? conhecimentos t?cnicos envolvidos de diversos aspectos, como a conex?o de circuitos, o conceito e o funcionamento de plataformas eletr?nicas Arduino, o que s?o os passos de um motor e como isso afeta a precis?o do mecanismo, etc. Evidencia-se aqui que muito embora este material abranja certa complexidade, a compreens?o de seus mecanismos de funcionamento podem ser devidamente aplicadas no Geogebra (software de livre distribui??o amplamente utilizado no ensino de matem?tica), onde o movimento dos bra?os do rob? podem ser facilmente constru?dos e colocados em movimento. Assim sendo, este trabalho abranger? tr?s etapas de desenvolvimento ap?s sua fundamenta??o te?rica: a primeira etapa consiste em apresentar os aspectos t?cnicos do Polargraph, a segunda consiste em apresentar os aspectos matem?ticos de seu funcionamento e a terceira dedica-se a aplica??es desta tecnologia e seus conceitos no meio did?ticoCoordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes)Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG)Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o Matem?tica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018.Being a low-cost, free-of-charge design machine and software that works on platforms with a wide audience reach, Polargraph is a drawbot made of simple parts and easy-to-acquire materials (mainly via internet), developed by the programmer, designer and Scottish inventor Sandy Noble. Its application in the classroom goes from the explanation of how the software works (all the mathematical concepts involved) to its drawings, made from cartesian coordinates, which leads to an immediate understanding that the movement of robots can only be done by means of mathematical calculations, and the more precise the calculations and the technology of the parts used, the more precise the movements, which can lead to di erent purposes. Obviously there is technical knowledge involved from various aspects, such as circuit connection, Arduino electronics platform concept and operation, what are the steps of a motor and how it a ects the accuracy of the mechanism, etc. It is evidenced here that although this material involves a certain complexity, the understanding of its working mechanisms can be properly applied in Geogebra (free-software widely used in math teaching), where the movement of the robot arms can be easily constructed and set in motion. Therefore, this work will cover three stages of development after its theoretical foundation: the rst stage consists of presenting the technical aspects of Polargraph, the second consists of presenting the mathematical aspects of its operation and the third is dedicated to applications of this technology and its concepts in the didatic environment

Eficiência do nitrato no desempenho de nadadores da categoria master de endurance no município de São Paulo

Introdução: Tem sido demonstrado que a suplementação com nitrato traz benefícios durante exercícios de alta intensidade, como a natação, pois acarreta um aumento na potência, no tempo de exaustão e melhora no desempenho em exercícios contrarrelógio. Objetivo: O propósito deste estudo foi verificar a eficiência do nitrato no desempenho de nadadores da categoria máster de endurance no município de São Paulo. Métodos: A amostra foi composta por 11 atletas, de ambos os gêneros, com idades entre 20 e 55 anos.  Os atletas foram submetidos a dois testes exaustivos, no primeiro dia ingerindo 500 ml de água, e no outro ingerindo 500 ml de suco de beterraba, ambos antes do treino. Foi avaliado o nível de desidratação e a percepção subjetiva de esforço (Escala de Borg). Resultados: Em relação à Escala de Borg, no teste ingerindo água, 36,3% dos atletas classificaram o treino como extremamente intenso, enquanto no teste com o suco de beterraba, 45,4% classificaram como intenso. No treino com a água, a média do percentual de perda de peso foi de 0,97% e a taxa de sudorese foi de 16,9 ml/min. Já com o suco de beterraba, a perda de peso foi levemente menor, de 0,93% e a taxa de sudorese de 15,6 ml/min. Conclusão: O consumo do suco de beterraba pode apresentar-se como uma alternativa positiva na discreta melhora da percepção do esforço em atletas de natação. ABSTRACTThe nitrate efficiency in the performance of the masters category in swimmers in Sao PauloIntroduction: It has been shown that nitrate supplementation is beneficial during high-intensity exercise, like in swimming, since it causes an increase in potency, in time of exhaustion and improved performance in exercises against the clock. Aim: The purpose of this study was to determine the nitrate efficiency in the performance of the masters category swimmers in Sao Paulo. Methods: The sample was composed of 11 athletes, of both genders, aged 20 to 55 years. The athletes were subject to two extensive testing, on the first day ingesting 500 ml of water and the other day ingesting 500 ml of beetroot juice, both before training. It was evaluated the level of dehydration and the subjective perception of effort (the Borg Scale). Results: In relation to the Borg Scale, the test ingesting water, 36.3% of the athletes rated the training as extremely intense, while test ingesting beetroot juice, 45.4% classified as intense. In training with water, the average weight loss percentage was 0.97% and the sweating rate was 16.9 ml / min. Already with beetroot juice, the weight loss was slightly lower, 0.93%, and the sweating rate was 15.6 ml / min. Conclusion: The consumption of beet juice can be presented as a positive alternative in the slight improvement of perceived exertion in swimming athletes

Trypanosoma cruzi Immune Response Modulation Decreases Microbiota in Rhodnius prolixus Gut and Is Crucial for Parasite Survival and Development

Trypanosoma cruzi in order to complete its development in the digestive tract of Rhodnius prolixus needs to overcome the immune reactions and microbiota trypanolytic activity of the gut. We demonstrate that in R. prolixus following infection with epimastigotes of Trypanosoma cruzi clone Dm28c and, in comparison with uninfected control insects, the midgut contained (i) fewer bacteria, (ii) higher parasite numbers, and (iii) reduced nitrite and nitrate production and increased phenoloxidase and antibacterial activities. In addition, in insects pre-treated with antibiotic and then infected with Dm28c, there were also reduced bacteria numbers and a higher parasite load compared with insects solely infected with parasites. Furthermore, and in contrast to insects infected with Dm28c, infection with T. cruzi Y strain resulted in a slight decreased numbers of gut bacteria but not sufficient to mediate a successful parasite infection. We conclude that infection of R. prolixus with the T. cruzi Dm28c clone modifies the host gut immune responses to decrease the microbiota population and these changes are crucial for the parasite development in the insect gut

Prospective study of patients with persistent symptoms of dengue in Brazil

Dengue is an arboviral infection clinically recognized as an acute and self-limited disease. Persistence of dengue symptoms is known, but it has been little studied. The aim of this study was to characterize persistent symptoms in 113 patients with dengue followed up clinically and by laboratory testing at a tertiary hospital. Symptoms that persisted for more than 14 days were observed in 61 (54.0%) patients, and six (6.2%) of them had symptoms for 6 months or more. The persistent symptoms identified were myalgia, weakness, hair loss, memory loss, reduced resistance to physical effort, headache, reasoning problems, arthralgia, sleepiness- and emotional lability. The progression to persistent symptoms was significantly associated with hospitalization, older age, more severe disease, the presence of bleeding and comorbidities upon univariate analysis. Upon multivariate analysis, the presence of persistent symptoms continued to be significantly associated only with increased age and dengue with warning signs. The platelet count during the acute phase of the disease was significantly lower in the group with persistent symptoms. In conclusion, the frequency of progression to persistent symptoms in dengue is relevant in patients seen at a tertiary hospital and the persistence of symptoms is more common in patients with dengue with warning signs

What traits are carried on mobile genetic elements, and why?

Although similar to any other organism, prokaryotes can transfer genes vertically from mother cell to daughter cell, they can also exchange certain genes horizontally. Genes can move within and between genomes at fast rates because of mobile genetic elements (MGEs). Although mobile elements are fundamentally self-interested entities, and thus replicate for their own gain, they frequently carry genes beneficial for their hosts and/or the neighbours of their hosts. Many genes that are carried by mobile elements code for traits that are expressed outside of the cell. Such traits are involved in bacterial sociality, such as the production of public goods, which benefit a cell's neighbours, or the production of bacteriocins, which harm a cell's neighbours. In this study we review the patterns that are emerging in the types of genes carried by mobile elements, and discuss the evolutionary and ecological conditions under which mobile elements evolve to carry their peculiar mix of parasitic, beneficial and cooperative genes

The traditional knowledge on stingless bees (Apidae: Meliponina) used by the Enawene-Nawe tribe in western Brazil

<p>Abstract</p> <p>Background</p> <p>This paper presents the Enawene-Nawe Society's traditional knowledge about stingless bees. The Enawene-Nawe are an Aruak speaking people, indigenous to the Meridian Amazon. Specifically, they live in the Jurema River hydrological basin, located in the northwestern region of the Mato Grosso state.</p> <p>Methods</p> <p>The stingless bees were sampled from two ecologically similar regions in the interior of Enawene-Nawe Land. The first sampling took place around the village, i.e., adjacent to houses, by the edge of the Iquê River, next to food leftovers, around human excrement, and simply when the insects were found flying or reposing on a human body. The second round of sampling happened from 29/10 to 02/11/94, during an expedition for honey collection that took place throughout the ciliar bushes of the Papagaio River, an important tributary of Juruena River. We sampled bees adjacent to their nests following the beehive inspection or during the honey extraction.</p> <p>In this work, the main bee species of the sub tribe Meliponina, which were handled by the Enawene-Nawe, was identified, and a brief ethnographic description of the honey collection expeditions and its social-cosmologic meaning for the group was done.</p> <p>Results and Discussion</p> <p>Similar to other indigenous people in Brazil, the Enawene-Nawe recognized 48 stingless bee species. They identified each bee species by name and specified each one's ecological niche. A brief ethnographic description of the honey collection expeditions and bees' social-cosmologic meaning for the group is included.</p> <p>Conclusion</p> <p>We concluded that, as an example of other indigenous people, the Enawene-Nawe classify and identify the bees based not only on their structure and morphological aspects but also on the ecological, etiological, and social characteristics of the species.</p