485 research outputs found
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
Transcriptional analysis of sex differences in hippocampal plasticity in the mouse.
The neuronal representation of experience as stable memories requires a process termed consolidation, which engages the hippocampus. Sexual dimorphisms in the performance of a number of tasks requiring hippocampus-dependent memory formation have previously been described. These sex differences are generally attributed to gonadal hormone-mediated mechanisms which impact on neuroanatomy and modulate memory formation. At the molecular level, memory consolidation requires de novo transcription, activating the transcription factor CREB. This activation can be accomplished by a variety of signalling pathways including the CaM kinase cascade. Male mutant mice bearing a genetic deletion of CaMKK/, an element of this cascade, are impaired in spatial memory formation in the Morris water maze (MWM), and fail to activate CREB after spatial training. Remarkably, female mutants performed equally to their WT counterparts, indicating a sex-specific requirement for this kinase in spatial memory consolidation. This mutant line was used as a tool to investigate dimorphisms in the molecular mechanisms underlying memory formation. First, comparison of hippocampal transcriptional profiles between WT and CaMKK/ mutants by Affymetrix Microarray analysis identified four CaMKK/ regulated genes in males. Second, quantitative real-time PCR was used to compare hippocampal transcriptional profiles of these genes in naive males and females, and after training in two hippocampus-dependent tasks: the MWM and contextual fear conditioning (CFC). This study identified three genes with altered transcription thirty minutes after spatial training in the MWM and CFC in male mice: PSF, Gaa1 and SRp20. Naive females expressed lower levels of all three genes than naive males, and two of them (Gaa1 and SRp20) were not regulated specifically by training in these tasks at the same time point in females. The work described in this thesis has identified two male-specific molecular markers for hippocampal activity, and provided insights into sexual dimorphisms in the molecular mechanisms underlying memory consolidation
Elliptical geometry and applications.
Programa de P?s-Gradua??o em Matem?tica em Rede Nacional. Departamento de Matem?tica, Instituto de Ci?ncias Exatas e Biol?gicas, Universidade Federal de Ouro Preto.Esse trabalho faz uma constru??o das geometrias: el?ptica dupla, projetiva e afim. Tamb?m
apresenta aplica??es das mesmas como um modelo para o movimento da superf?cie terrestre
e na identifica??o de c?nicas. Al?m disso, possui uma utiliza??o de cada uma dessas
aplica??es no ensino m?dio como meio de motivar os alunos no estudo de geometrias n?o
euclidianas.This work makes a construction of the geometries: Double Eliptica, Projective, and Affine.
It presents applications as the model for the movement of the terrestrial surface and in the
identification of conics. In addition, has a use of each of these applications in high school with a
means to motivate students in the study of non-Euclidean geometries
Outros tempos, outras hist?rias : kair?s, manifesto, crise.
Programa de P?s-Gradua??o em Hist?ria. Departamento de Hist?ria, Instituto de Ci?ncias Humanas e Sociais, Universidade Federal de Ouro Preto.Toda concep??o de hist?ria est? sustentada em uma compreens?o de tempo. Esta tese prop?e a categoria historicidades kairol?gicas para caracterizar as modalidades da experi?ncia da hist?ria cujo sentido temporal se funda na no??o de kair?s. Argumento que as historicidades kairol?gicas possuem um estatuto meta-hist?rico: por um lado, a categoria delimita uma dimens?o espec?fica da historicidade da exist?ncia em geral; por outro, ela abre tal dimens?o para a compreens?o hist?rica, sendo aplic?vel para a an?lise de objetos que manifestam na linguagem formas kairol?gicas de temporaliza??o da hist?ria. A hip?tese ? que o manifesto, como g?nero textual, se notabiliza pela capacidade de organizar poeticamente as historicidades kairol?gicas. A rela??o entre kair?s e manifesto se d? pela media??o de um terceiro conceito operat?rio: a crise. Defendo que o sentido hist?rico-temporal de crise somente pode ser adequadamente compreendido a partir da assimetria entre cronos e kair?s. Portanto, a constru??o da categoria historicidades kairol?gicas ? feita por meio da demonstra??o da contiguidade l?gica, temporal e hist?rica existente entre kair?s, manifesto e crise. A tese desdobra os potenciais anal?ticos das historicidades kairol?gicas por meio de uma dupla abordagem: uma exposi??o sint?tica da hist?ria do g?nero manifest?rio; e uma an?lise verticalizada do manifesto The Kairos Document (?frica do Sul, 1985). Ao fim, aponto para a potencial utilidade da categoria proposta na tese para pensar um tra?o central da autocompreens?o hist?rica das sociedades contempor?neas globais, a saber, que vivemos ?em tempos de crise?.Every conception of history is grounded on an understanding of time. This thesis proposes the category kairological historicities to characterize the modalities of historical experience whose temporal meaning is based on the notion of kairos. I argue that the kairological historicities is a meta-historical category: on the one hand, it delimitates a specific dimension proper to the historicity of existence in general; on the other, it opens up that dimension to historical understanding, thus being useful to analyzing objects that manifest in language the kairological forms of temporalizing history. The hypothesis is that the manifesto, as a textual genre, is notable for its ability to organize poetically the kairological historicities. The relationship between manifesto and kairos occurs through the mediation of a third, operative concept: crisis. I claim that the historical-temporal meaning of crisis can only be properly grasped from the asymmetry between cronos and kairos. Therefore, the construction of the kairological historicities as a meta-historical category is made by demonstrating the logical, temporal and historical contiguity between kairos, manifesto, and crisis. The thesis unfolds the analytical potentials of the proposed category through a double approach: a synthetic exposition of the history of the genre; and a vertical analysis of the manifesto The Kairos Document (South Africa, 1985). In the end, I point to the potential usefulness of the kairological historicities to think about a central feature in the historical self-understanding of contemporary global societies, namely, that we are living ?in times of crisis?
DXA assessment
Accurate assessment of body composition is an important issue among athletes. Different methodologies generate controversial results, leading to a deep uncertainty on individual exercise prescriptions. Thus, this study aims to identify the differences between field methods, such as bioelectrical impedance (BIA) and skinfold assessment, with a clinical method, highly accurate, dual-energy X-ray absorptiometry (DXA), among elite young football players. Thirty-eight male football players with a mean (sd) age of 16.7 (0.87) years, involved in the Portuguese national competition of U16 (n = 13) and U19 (n = 25), were evaluated and objective measures of body composition, muscle strength and football skills were collected by trained specialists. Body composition was assessed using BIA (Tanita BC-418, Tanita Corp., Tokyo, Japan), in agreement with all the evaluation premises. Additionally, all athletes were evaluated using the clinical method
DXA (Hologic Inc., Waltham, MA, USA). Among the U19 athletes, three skinfold sites (SKF) were assessed: chest, abdomin and thigh. The Spearman correlation coefficients and the mean difference between methods were calculated. The agreement between both methods was analyzed using Bland-Altman plots. Among the evaluated athletes, lower mean values of body fat % were found using BIA as a method of body composition assessment compared with DXA (12.05 vs. 15.58 for U16; 11.97 vs. 14.16 for U19). Despite the moderate correlation between methods (r = 0.33) to estimate the percentage of total fat, the median of the difference (DXA vs. BIA) was relevant in clinical terms, with 2.90% and 1.47% for U16 and U19 athletes, respectively. Stronger correlations were found between the sum of the SKF and DXA fat estimation (r = 0.68). The Bland-Altman plots showed a clear underestimation in the evaluations using the BIA, namely among athletes with better body composition profiles (8%?12% of fat). Using BIA, an underestimation of body fat assessment was
observed among 94.5% of the athletes with less than 12% body fat mass. Among the evaluated athletes, fat mass was underestimated at a median value of 2.21% using BIA in comparison with DXA. The sum of the SKF showed a stronger correlation with the reference method (DXA) (r = 0.68) than BIA.D915-7373-ED16 | Cesar LeaoN/
Soft Skills como Componente Fundamental na Educa??o de T?cnicos em Enfermagem: Abordagens Pedag?gicas Inovadoras
O cultivo das soft skills na trajet?ria de um t?cnico em enfermagem ? um componente essencial
para garantir uma carreira duradoura e bem-sucedida. A promo??o dessas habilidades durante
o per?odo de forma??o desempenha um papel fundamental no processo educacional, exigindo
que os alunos mergulhem profundamente no desenvolvimento dessas compet?ncias. Essa
imers?o n?o apenas enriquece a aprendizagem, mas tamb?m proporciona experi?ncias valiosas
que se estendem al?m do ?mbito profissional, influenciando positivamente a vida pessoal dos
estudantes. Nesse contexto, este trabalho consiste em uma proposta de interven??o pedag?gica
sobre a implementa??o de ferramentas para o desenvolvimento de soft skills no curso T?cnico
em Enfermagem. A metodologia para o desenvolvimento deste trabalho consiste em uma
abordagem descritiva, com aplica??o direta durante o per?odo de forma??o. Desse modo,
espera-se que a referida interven??o pedag?gica contribua no desenvolvimento de
compet?ncias e habilidades associadas ?s compet?ncias t?cnicas dos alunos do Curso T?cnico
em Enfermagem.n?o h
Cytogenetics of Melitoma segmentaria (Fabricius, 1804) (Hymenoptera, Apidae) reveals differences in the characteristics of heterochromatin in bees.
To date, more than 65 species of Brazilian bees (of the superfamily Apoidea) have been cytogenetically studied, but only a few solitary species have been analyzed. One example is the genus Melitoma Lepele?tier & Serville, 1828, for which there is no report in the literature with regard to cytogenetic studies. The objective of the present study is to analyze the chromosome number and morphology of the species Melitoma segmentaria (Fabricius, 1804), as well as to determine the pattern of heterochromatin dis?tribution and identify the adenine?thymine (AT)- and guanine?cytosine (GC)-rich regions. Melitoma segmentaria presents chromosome numbers of 2n=30 (females) and n=15 (males). With C-banding, it is possible to classify the chromosomes into seven pseudo-acrocentric pairs (AM), seven pseudo-acrocentric pairs with interstitial heterochromatin (AMi), and one totally heterochromatic metacentric pair (Mh). Fluo?rochrome staining has revealed that heterochromatin present in the chromosomal arms is rich in GC base pairs (CMA3+) and the centromeric region is rich in AT base pairs (DAPI+). The composition found for Melitoma diverges from the pattern observed in other bees, in which the heterochromatin is usually rich in AT. In bees, few heterochromatic regions are rich in GC and these are usually associated with or localized close to the nucleolus organizer regions (NORs). Silver nitrate impregnation marks the heterochromatin present in the chromosome arms, which makes identification of the NOR in the chromosomes impos?sible. As this technique reveals proteins in the NOR, the observation that is made in the present study suggests that the proteins found in the heterochromatin are qualitatively similar to those in the NOR
Geographical distribution patterns and niche modeling of the iconic leafcutter ant Acromyrmex striatus (Hymenoptera: Formicidae).
Ants are considered one of the most successful groups in the planet?s evolutionary history. Among them highlights
the fungus-farming ants of the genera Atta and Acromyrmex that occur throughout most of the Americas.
Within the Acromyrmex genus, the species A. striatus distinguishes from other Acromyrmex species as its morphology
and karyotype differ from its congeners. This species is found in open environments of dry climate in
the southern States of Brazil, Argentina, Paraguay and Uruguay; however, little is known about the current distribution
of the species. This article aimed to investigate the current distribution of the species by compiling its
known distribution and discussing its distributional range. To achieve this, published and unpublished data obtained
through a literature search and active collections in various locations were compiled. Published and
unpublished data revealed that 386 colonies were recorded, distributed across four countries where its occurrence
is known. Environmental factors, such as temperature, humidity, soil type and vegetation, as well as
historical geological and climate events that have modified Earth?s surface may have influenced species distribution
patterns. In the Neotropics, the environmental factors that most impacted the distribution of species
were the glaciation periods that occurred in the Quaternary, leading to a great migratory process. These factors
may have contributed to the current geographical distribution of A. striatus
Osteosarcoma contains a subpopulation of cancer stem-like cells that are highly resistant to radiotherapy
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