Procedural embodiment and magic in linear equations

How do students think about algebra? Here we consider a theoretical framework which builds from natural human functioning in terms of embodiment – perceiving the world, acting on it and reflecting on the effect of the actions – to shift to the use of symbolism to solve linear equations. In the main, the students involved in this study do not encapsulate algebraic expressions from process to object, they do not solve ‘evaluation equations’ such as by ‘undoing’ the operations on the left, they do not find such equations easier to solve than , and they do not use general principles of ‘do the same thing to both sides.’ Instead they build their own ways of working based on the embodied actions they perform on the symbols, mentally picking them up and moving them around, with the added ‘magic’ of rules such as ‘change sides, change signs.’ We consider the need for a theoretical framework that includes both embodiment and process-object encapsulation of symbolism and the need for communication of theoretical insights to address the practical problems of teachers and students

The emergence of <i>Pax7</i>-expressing muscle stem cells during vertebrate head muscle development

Pax7 expressing muscle stem cells accompany all skeletal muscles in the body and in healthy individuals, efficiently repair muscle after injury. Currently, the in vitro manipulation and culture of these cells is still in its infancy, yet muscle stem cells may be the most promising route towards the therapy of muscle diseases such as muscular dystrophies.It is often overlooked that muscular dystrophies affect head and body skeletal muscle differently. Moreover, these muscles develop differently. Specifically, head muscle and its stem cells develop from the non-somitic head mesoderm which also has cardiac competence. To which extent head muscle stem cells retain properties of the early head mesoderm and might even be able to switch between a skeletal muscle and cardiac fate is not known. This is due to the fact that the timing and mechanisms underlying head muscle stem cell development are still obscure. Consequently, it is not clear at which time point one should compare the properties of head mesodermal cells and head muscle stem cells.To shed light on this, we traced the emergence of head muscle stem cells in the key vertebrate models for myogenesis, chicken, mouse, frog and zebrafish, using Pax7 as key marker. Our study reveals a common theme of head muscle stem cell development that is quite different from the trunk. Unlike trunk muscle stem cells, head muscle stem cells do not have a previous history of Pax7 expression, instead Pax7 expression emerges de-novo. The cells develop late, and well after the head mesoderm has committed to myogenesis. We propose that this unique mechanism of muscle stem cell development is a legacy of the evolutionary history of the chordate head mesoderm

Automated Fact Checking in the News Room

Fact checking is an essential task in journalism; its importance has been highlighted due to recently increased concerns and efforts in combating misinformation. In this paper, we present an automated fact-checking platform which given a claim, it retrieves relevant textual evidence from a document collection, predicts whether each piece of evidence supports or refutes the claim, and returns a final verdict. We describe the architecture of the system and the user interface, focusing on the choices made to improve its user-friendliness and transparency. We conduct a user study of the fact-checking platform in a journalistic setting: we integrated it with a collection of news articles and provide an evaluation of the platform using feedback from journalists in their workflow. We found that the predictions of our platform were correct 58\% of the time, and 59\% of the returned evidence was relevant

Determinants of Land Use/Cover Change in the Iberian Peninsula (1990–2012) at Municipal Level

This work analyzes the determinants associated with main land use/cover changes in the Iberian Peninsula during the 1990–2012 period using a decision tree model. Our main objective is to identify broad-scale patterns that associate the characteristics of geographic areas with the dominant land use/cover change process based on CORINE Land Cover (Coordination of Information on the Environment) and defined in a previously published work. Biophysical, structural and socioeconomic variables were considered as potentially explanatory of the dominant change process at municipal scale. The resulting model allowed identification of a common pattern in Portugal and Spain (urbanization being highly associated to areas already densely populated in the previous period), but also some diverging ones. In particular, dominant trends in Portuguese territory appear to be highly determined by wildfire occurrence. In contrast, Spanish municipalities showed more diverse patterns, usually associated to biophysical determinants like average forest productivity or average terrain slopeS

Evaluation of device reliability based on accelerated tests

Reliability evaluation based on degradation is very useful in systems with scarce failures. In this paper a new degradation model based on Weibull distribution is proposed. The model is applied to the degradation of Light Emitting Diodes (LEDs) under different accelerated tests. The results of these tests are in agreement with the proposed model and reliability function is evaluated

Fundação Municipal de Desenvolvimento Comunitário e Faculdade de Educação Física : uma parceria que vem dando certo

Este texto tem o objetivo de divulgar a parceria que se desenvolveu entre a Faculdade de Educação Física e a Fundação Municipal de Desenvolvimento Comunitário que possibilitou a abertura de novos espaços, na cidade de Goiânia, de intervenção no campo da educação física e esportes. _________________________________________________________________________________ ABSTRACTThis text has an objective to spread the partnership that has been developed between the Faculty of Physical Education and the Municipal Foundation of Community Development that possibited the opening of new spaces, in the city of Goiania, to intervention in the area of Physical Education and Sports

Overview of Stingless Bees in Brazil (Hymenoptera: Apidae: Meliponini)

Species richness of stingless bees (Hymenoptera: Apidae: Meliponini) was organized and updated from previously published data. From this research, we found 28 genera with 259 valid species and 62 undescribed species, in addition, brief comments on the classification used and geographical occurrences were included

Sistemática de Scaura Schwarz, 1938 (Hymenoptera: Apidae, Meliponini), com notas biológicas

Systematics of Scaura Schwarz, 1938 (Hymenoptera: Apidae: Meliponini), with biological notes. Scaura Schwarz 1938 is a neotropical little diverse and distributed genus. It’s widely composed of workers with hind basitarsus as wide as or wider than their tibia. The genus comprised five valid species, but with evidence that there was a complex of species to be described. It was obtained dry specimens, in various national and foreign collections, and studying this material, a taxonomic revision and a phylogenetic analysis of all species of the genus were proposed, resulting in a total of seven valid species: with three new species and synonymy of Scaura tenuis (Ducke, 1916) under Scaura latitarsis (Friese, 1900). An Illustrated worker identification key was proposed, and each species previously described was redescribed to have a standardized description with the addition of males and queens when possible. Every species had its geographic distribution updated, as well as a compilation of data on nesting biology and behavior. The phylogenetic analysis resulted in Scaura as a monophyletic genus, and Schwarzula Moure, 1946 as its sister group. It is noteworthy that the relationship between the Scaura species with short metasoma still needs to have phylogenetic relationships best established. The Scaura species with short metasoma needs more morphological caracteres and new phylogenetic analyses for suggest better relationships.Scaura Schwarz, 1938 é um gênero neotropical pouco diversificado e amplamente distribuído, composto por operárias com basitarsos metatorácicos tão largos quanto ou mais largos que as respectivas tíbias. O gênero compreendia cinco espécies válidas, mas com indícios de que havia um complexo de espécies a serem descritas. Com a obtenção de espécimes, em via seca, de várias coleções nacionais e estrangeiras, e estudo desse material, foi proposta uma revisão taxonômica, bem como uma análise filogenética de todas as espécies do gênero, resultando assim, em um total de sete espécies válidas: com três novas e a sinonímia de Scaura tenuis (Ducke, 1916) sob Scaura latitarsis (Friese, 1900). Foi proposta uma chave ilustrada de identificação de operárias e cada espécie já descrita foi redescrita para haver uma padronização com a adição da descrição de machos e rainhas, quando possível. Cada uma dessas espécies propostas possui registros geográficos atualizados, bem como uma compilação de dados sobre a biologia de nidificação e comportamento. A análise filogenética constatou o monofiletismo do gênero, tendo como grupo irmão Schwarzula Moure, 1946. Entretanto, as espécies de Scaura com metassoma curto ainda precisam ter as relações filogenéticas melhores estabelecidas