128 research outputs found

    Envolver os alunos de forma produtiva em aulas de ciências físicas: evidências para uma proposta de uma ferramenta para ajudar os professores

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    A qualidade das aprendizagens dos alunos nas aulas de Ciências Físicas pode melhorar se a mediação do professor atribuir um papel fundamental ao envolvimento produtivo dos alunos. A partir de narrações sobre a mediação do professor em contexto de sala de aula, analisou-se o envolvimento dos alunos nas aulas de Ciências Físicas, o esforço do professor para induzir esse envolvimento, bem como indicadores de produtividade dos alunos. Com base nas evidências empíricas obtidas, elaborou-se uma proposta de ferramenta de trabalho, adaptável, para apoiar os professores na identificação de indicadores do envolvimento produtivo dos seus alunos na disciplina e de possíveis modos de os professores envolverem os alunos na disciplina de modo produtivo

    Utilização de contextos científicos e tecnológicos no ensino das ciências físicas : conhecer para valorizar

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    Este estudo enquadra-se na temática da mediação do ensino das ciências, focando a integração de contextos científicos e tecnológicos (CT) em aulas de ciências físicas (CF). Tem por principal objectivo aprofundar o conhecimento sobre as formas e os modos como os contextos CT são tratados em sala de aula. Neste trabalho apresentamos as evidências encontradas em aulas de 4 professores de CF. Como instrumento de recolha de dados utilizámos as narrações dos professores sobre a exploração de situações do quotidiano para trabalhar conceitos, leis e princípios de forma a melhorar a qualidade das aprendizagens dos alunos. Com base na análise das narrações e nas categorias emergentes propomos as linhas gerais de uma ferramenta de ajuda aos professores

    Using educational robotics in pre-service teacher training : orchestration between an exploration guide and teacher role

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    The proper integration of technology in teaching and learning processes must consider the role of teachers and students, as well as the design of tasks and the context in which they are implemented. Teachers’ perceived self-efficacy significantly influences their willingness to integrate educational robotics (ER) into their practice, so initial teacher training should provide opportunities for teachers to participate in structured activities that integrate ER. In this study, a class of pre-service teachers from an initial teacher training programme were provided with their first contact with an ER platform through the use of a simulator. We present the design process of a student exploration guide and teacher guide, developed over three iterative cycles of implementation, assessment and redesign. The analysis of the data collected allowed for improvements in the design of the tasks, the graphic component of the student exploration guide, and more precise indications for the teacher’s actions. The main contribution of this study is the chain orchestration between the simulator, student exploration guide and teacher guide, which allowed pre-service teachers to solve a set of challenges of increasing complexity, thereby progressively decreasing their difficulties and contributing to an adequate integration of ER in their future teaching practices.info:eu-repo/semantics/publishedVersio

    NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

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    Incluye contenido parcial de los autoresAbstract.Mammalian carnivores are considered a key group in maintaining ecologicalhealth and can indicate potential ecological integrity in landscapes where they occur. Carni-vores also hold high conservation value and their habitat requirements can guide managementand conservation plans. The order Carnivora has 84 species from 8 families in the Neotropicalregion: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; andUrsidae. Herein, we include published and unpublished data on native terrestrial Neotropicalcarnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTRO-PICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data wereobtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organi-zations, and private consultants. Data were collected using several methods including cameratrapping, museum collections, roadkill, line transect, and opportunistic records. Literature(peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated inthis compilation. Most of the data set consists of detection data entries (n=79,343; 79.7%) butalso includes non-detection data (n=20,262; 20.3%). Of those, 43.3% also include count data(n=43,151). The information available in NEOTROPICAL CARNIVORES will contribute tomacroecological, ecological, and conservation questions in multiple spatio-temporal perspec-tives. As carnivores play key roles in trophic interactions, a better understanding of their distri-bution and habitat requirements are essential to establish conservation management plans andsafeguard the future ecological health of Neotropical ecosystems. Our data paper, combinedwith other large-scale data sets, has great potential to clarify species distribution and relatedecological processes within the Neotropics. There are no copyright restrictions and no restric-tion for using data from this data paper, as long as the data paper is cited as the source of theinformation used. We also request that users inform us of how they intend to use the data

    Influence of passage number on the impact of the secretome of adipose tissue stem cells on neural survival, neurodifferentiation and axonal growth

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    Mesenchymal stem cells (MSCs), and within them adipose tissue derived stem cells (ASCs), have been shown to have therapeutic effects on central nervous system (CNS) cell populations. Such effects have been mostly attributed to soluble factors, as well as vesicles, present in their secretome. Yet, little is known about the impact that MSC passaging might have in the secretion therapeutic profile. Our aim was to show how human ASCs (hASCs) passage number influences the effect of their secretome in neuronal survival, differentiation and axonal growth. For this purpose, post-natal rat hippocampal primary cultures, human neural progenitor cell (hNPCs) cultures and dorsal root ganglia (DRGs) explants were incubated with secretome, collected as conditioned media (CM), obtained from hASCs in P3, P6, P9 and P12. Results showed no differences when comparing percentages of MAP-2 positive cells (a mature neuronal marker) in neuronal cultures or hNPCs, after incubation with hASCs secretome from different passages. The same was observed regarding DRG neurite outgrowth. In order to characterize the secretomes obtained from different passages, a proteomic analysis was performed, revealing that its composition did not vary significantly with passage number P3 to P12. Results allowed us to identify several key proteins, such as pigment epithelium derived factor (PEDF), DJ-1, interleucin-6 (IL-6) and galectin, all of which have already proven to play neuroprotective and neurodifferentiating roles. Proteins that promote neurite outgrowth were also found present, such as semaphorin 7A and glypican-1. We conclude that cellular passaging does not influence significantly hASCs's secretome properties especially their ability to support post-natal neuronal survival, induce neurodifferentiation and promote axonal growth.Prémios Santa Casa Neurociências - Prize Melo e Castro for Spinal Cord Injury Research (MC-17-2013 and MC-04-2017), Canada Research Chair in Biomedical Engineering (LAB), Northern Portugal Regional Operational Programme (NORTE 2020),, European Regional Development Fund (FEDER), Competitiveness Factors Operational Programme (COMPETE), National Mass Spectrometry Network (RNEM)info:eu-repo/semantics/publishedVersio

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Residential mobility of middle-class and popular sectors: the city of Buenos Aires as an arrival destination

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    El artículo reflexiona acerca de los patrones de movilidad residencial de individuos y hogares de sectores populares y medios que residen en dos zonas de la Ciudad de Buenos Aires configuradas en torno a patrones disimiles de segregación. La movilidad residencial es un lente privilegiado para evidenciar de qué modo la experiencia de la clase es producida y reproducida en los modos de habitar. Mediante un abordaje cualitativo y biográfico hemos analizado las especificidades que presentan las movilidades residenciales de los diferentes sectores sociales. Se identifican patrones en tres dimensiones de la movilidad residencial: su espacialidad, los arreglos residenciales que los hogares despliegan y las motivaciones que guían sus desplazamientos. Los hallazgos presentados dan cuenta de los efectos que produce la posición en la estructura social sobre la movilidad residencial, así como su interacción con la propia estructuración del espacio.The article reconstructs residential mobility patterns of individuals and households from popular and middle-class sectors residing in two areas of the city of Buenos Aires, configured around dissimilar segregation patterns. Residential mobility is a powerful lens to show how the social class experience is produced and reproduced in modes of dwelling. Through a qualitative and biographical approach, we analyzed the specificities presented by residential mobilities of different social sectors. We identified patterns in the three dimensions of residential mobility: spatiality, the residential arrangements that households employ, and the motivations that guide their movements. The findings show the effects that the position in the social structure has on residential mobility, as well as its interaction with the spatial structure itself.publishedVersionFil: Cosacov, Andrea. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Cosacov, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas; Argentina.Fil: Di Virgilio, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación Gino Germani; Argentina.Fil: Najman, Mercedes. Universidad de Buenos Aires. Facultad de Ciencias Sociales; Argentina.Fil: Di Virgilio, María Mercedes. Universidad de Buenos Aires. Facultad de Ciencias Sociales; Argentina.Fil: Najman, Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación Gino Germani; Argentina

    Talents from Abroad. Foreign Managers and Productivity in the United Kingdom.

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    In this paper, we test the contribution of foreign management on firms’ competitiveness. We use a novel dataset on the careers of 165,084 managers employed by 13,106 companies in the United Kingdom in the period 2009-2017. We find that a domestic manufacturing firm becomes on average between 9% and 12% more productive after hiring at least one foreign manager. Interestingly, productivity gains by domestic firms after recruiting foreign managers are similar in magnitude to gains after foreign acquisitions as from previous literature. Eventually, we do not find significant gains by foreign-owned firms hiring foreign managers. Our identification strategy combines difference-in-difference and matching techniques to challenge reverse causality. We proxy firms’ competitiveness either by total factor productivity or by technical efficiency derived from stochastic frontier analyses. Eventually, we argue that limits to the circulation of talents, as for example in case of a Brexit event, may hamper the allocation of labor productive resources
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