244 research outputs found

    Activation and inhibition of bimanual movements in school-aged children

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    The development of motor activation and inhibition was compared in 6-to-12 year-olds. Children had to initiate or stop the externally paced movements of one hand, while maintaining that of the other hand. The time needed to perform the switching task (RT) and the spatio-temporal variables show different agerelated evolutions depending on the coordination pattern (inor anti-phase) and the type of transition (activation, selective inhibition, non selective inhibition) required. In the anti-phase mode, activation perturbs the younger subjects' responses while temporal and spatial stabilities transiently decrease around 9 years when activating in the in-phase mode. Aged-related changes differed between inhibition and activation in the antiphase mode, suggesting either the involvement of distinct neural networks or the existence of a single network that is reorganized. In contrast, stopping or adding one hand in the in-phase mode shows similar aged-related improvement. We suggest that selectively stopping or activating one arm during symmetrical coordination rely on the two faces of a common processing in which activation could be the release of inhibitio

    Ranking and clustering of nodes in networks with smart teleportation

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    Random teleportation is a necessary evil for ranking and clustering directed networks based on random walks. Teleportation enables ergodic solutions, but the solutions must necessarily depend on the exact implementation and parametrization of the teleportation. For example, in the commonly used PageRank algorithm, the teleportation rate must trade off a heavily biased solution with a uniform solution. Here we show that teleportation to links rather than nodes enables a much smoother trade-off and effectively more robust results. We also show that, by not recording the teleportation steps of the random walker, we can further reduce the effect of teleportation with dramatic effects on clustering.Comment: 10 pages, 7 figure

    Cytogenetics of four foam-nesting frog species of the Physalaemus gracilis group (Anura, Leptodactylidae)

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    Intending to increase the knowledge about cytogenetics of Physalaemus and the sparsely studied P. gracilis group, we analyzed the karyotypes of P. carrizorum, P. gracilis, P. lisei, and P. sp. aff. gracilis. We studied chromosome morphology, heterochromatin patterns, Ag-NORs location and mapped the repetitive DNA sequence PcP190. All species showed diploid karyotypes composed of 22 bi-armed chromosomes and similar C- bands and Ag-NOR patterns. C-bands were mainly centromeric and pericentromeric; non-centromeric C-bands were detected on the telomeres of pair 1 in P. lisei, although polymorphic, and interstitially on pair 10 of P. gracilis. This last character is useful to distinguish P. gracilis from its sibling species P. sp. aff. gracilis. The Ag- NOR sites were detected on the long arms of chromosome pair 8 but with a variable position among species. Clusters of PcP190 showed centromeric and pericentromeric positions coincident with conspicuous C-bands, on pairs 2 and 9 in P. gracilis and P. sp. aff. gracilis, pair 3 in P. carrizorum, and pair 7 in P. lisei. These results significantly increase the knowledge about Physalaemus cytogenetics and encourage further studies on the satellite PcP190 in other genera of Leiuperinae to better understand its taxonomic distribution and the evolutionary dynamics.Fil: Ferro, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Taffarel, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Tomatis, Cristian Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Borteiro, Claudio. Ministerio de Educación y Cultura. Museo Nacional de Historia Natural; UruguayFil: Kolenc, Francisco. Ministerio de Educación y Cultura. Museo Nacional de Historia Natural; UruguayFil: Pretto Gatto, Kaleb. Universidade Estadual de Campinas. Instituto de Biología; BrasilFil: Lourenço, Luciana B.. Universidade Estadual de Campinas. Instituto de Biología; BrasilFil: Baldo, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentin

    Crescimento e desenvolvimento de pessegueiros 'Chimarrita' e 'Maciel' sobre diferentes porta-enxertos e locais de cultivo.

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    Objetivou-se com o presente trabalho avaliar a influência dos porta-enxertos no que se refere ao crescimento vegetativo e desenvolvimento dos pessegueiro 'Chimarrita' e 'Maciel' em três locais de cultivo. O experimento foi desenvolvido em três locais de cultivo: 1 (Embrapa Uva e Vinho), 2 (EEA UFRGS) e 3 (CAP UFPel), em três anos. As cultivares de pessegueiro utilizadas foram: 'Chimarrita' e 'Maciel' enxertadas sobre seis porta-enxertos ('Aldrighi', 'Capdeboscq', 'Flordaguard', 'Nemaguard', 'Okinawa' e Umezeiro), no espaçamento 1,5 X 5,0m e conduzidas no sistema em ?V?. Foram avaliados: volume de copa, diâmetro de tronco, massa fresca da poda, produção por planta acumulada, comprimento, espessura, gemas floríferas e densidade florífera do ramo produtivo. Também foi avaliado de forma visual o ponto de enxertia. O porta-enxerto Umezeiro induziu menor vigor nos três locais de cultivo estudados e na média dos três anos. Ele pode ser indicado para utilização sob 'Maciel' nas condições edafoclimáticas do local 3. No local 1 o porta-enxerto, 'Nemaguard' possui alto vigor e maior produção acumulada, sendo o mais indicado. Já para o local 2, os porta-enxertos 'Capdeboscq', 'Okinawa' e 'Flordaguard' são os mais indicados. Os porta-enxertos afetam as características de crescimento e desenvolvimento das cultivares 'Chimarrita' e 'Maciel', o vigor destas é menor sobre o portaenxerto Umezeiro nos três locais de cultivo. Todos os portaenxertos podem ser indicados para os três locais de cultivo, com exceção do Umezeiro, que somente pode ser indicado em combinação com a cultivar 'Maciel' no local 3

    Nintedanib Treatment for Idiopathic Pulmonary Fibrosis Patients Who Have Been Switched from Pirfenidone Therapy: A Retrospective Case Series Study

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    BACKGROUND: The efficacy and effectiveness of nintedanib as a first-line therapy in idiopathic pulmonary fibrosis (IPF) patients have been demonstrated by clinical trials and real-life studies. Our aim was to examine the safety profile and effectiveness of nintedanib when it is utilized as a second-line treatment in subjects who have discontinued pirfenidone. METHODS: The medical charts of 12 patients who were switched from pirfenidone to nintedanib were examined retrospectively. The drug's safety was defined by the number of adverse events (AEs) that were reported; disease progression was evaluated based on the patient's vital status and changes in forced vital capacity (FVC) at 12-month follow-up. RESULTS: The numbers of patients experiencing AEs and of the AEs per patient in our study group didn't significantly differ with respect to a group of 56 individuals who were taking nintedanib as a first-line therapy during the study period (5/12 vs. 22/56; p = 0.9999, and 0.00 (0.00-1.00) vs. 0.00 (0.00-3.00); p = 0.517, respectively). Two out of the 3 patients who had been switched to nintedanib due to a rapid disease progression showed stabilized FVC values. CONCLUSIONS: Nintedanib was found to have an acceptable safety profile in the majority of the IPF patients switched from pirfenidone. Prospective studies are warranted to determine if the drug can effectively delay disease progression in these patients

    History and philosophy of science in Biology teaching

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    Neste trabalho, buscamos evidenciar a concepção de História da Biologia que é veiculada nos livros didáticos. Para tanto, analisamos três coleções de livros de Biologia destinados ao Ensino Médio, e alguns livros universitários usados em cursos de formação de professores. Ao analisar este material curricular foi possível observar que a história apresentada é desvinculada do contexto cultural de cada período histórico, o que pode levar o aluno a construir uma falsa representação da ciência e do fazer científico.In this work, we search forto evidences the conception of the History of Biology being is propagated in textbooks. We analyze three Biology book collections designed estined forto middle schooledium education, and some university books used in teacher education courses. When analyzing this curricular material it was possible to observe that the history of biology presented is disengaged from entailedofthe cultural context of each historical period, and this what can lead the student to construct a false representation of science and of scientific meaning making

    Avaliação de RPAs para pulverização em diferentes culturas

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    The present work had as objective to study and to validate the application of defenses through RPAs (Remotely Piloted Aircraft), commonly denominated Drones. The experiment happened at APTA East Center in Ribeirão Preto, Sao Paulo. The herbicide solution glyphosate 1.5 kg ha-1 (Roundup WG®) was used using 15 L ha-1 of syrup volume. The RPA that overflew the study area at three different altitudes together with three different spray nozzle models in a range of 50 m x 5 m, with water-sensitive papers being distributed in these bands to verify the size, quantity and distribution of drops that fell on the plants. Once the information was counted, it was expected that it would be possible to create different application models, leading to greater efficiency and effectiveness of the applications. In addition, avoid waste of defense, contributing to decrease environmental impacts and increase safety in the field (lower risk of intoxication). The results allowed to identify competitive advantages, highlighting the practicality and speed, besides allowing localized control of weeds, without the need of tractors, which increases soil compaction and requires greater investment in equipment. From these results, use protocols will beestablished for various agricultural crops, such as: Peanut (Arachis hypogaea L.), Sugarcane (Saccharum officinarum L.), Soya (Glycine max L.), Maize (Zea mays).O presente trabalho teve como objetivo estudar e validar a aplicação de defensivos através de RPAs (Aeronave Remotamente Pilotadas), comumente denominadas de Drones. O experimento foi realizado na APTA Centro Leste no município do Ribeirão Preto, SP. Foi utilizado a: solução de herbicida glifosate 1.5 kg ha-1 (Roundup WG®) utilizando 15 L ha-1 de volume de calda. O RPA que sobrevoou a área de estudo em três diferentes altitudes, juntamente com três diferentes modelos de bicos pulverizadores em uma faixa compreendida de 50 m x 5 m, sendo que nessas faixas foram distribuídos papéis sensíveis à água, para verificar o tamanho, quantidade e distribuição de gotas que caíram sobre as plantas. Uma vez contabilizadas as informações, esperou-se que fosse possível criar diferentes modelos de aplicações, levando a uma maior eficiência e eficácia das aplicações. Além disso, evitar desperdício de defensivo, contribuindo para diminuição dos impactos ambientais e aumento da segurança no campo (menor risco de intoxicações). Os resultados permitiram identificar vantagens competitivas, com destaque para a praticidade e rapidez, além de permitir controle localizado de plantas daninhas, sem a necessidade de uso de tratores, o qual aumenta compactação do solo e requer maior investimento em equipamentos. A partir destes resultados, serão estabelecidos protocolos de utilização para diversas culturas agrícolas, tais como: Amendoim (Arachis hypogaea L.), Cana-de-açúcar (Saccharum officinarum L.), Soja (Glycine max L.), Milho (Zea mays)

    Uso de infravermelho próximo para estimativa das falhas no estande e produtividade do amendoim

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    This research aims to study the use of NIR images for peanut production estimates in three different planting processes (conventional tillage, no-tillage, and planting Rip Strip) relating productivity information with extracted parameters Orthophoto generated by an Air Vehicle No manned (UAV). The images 0.2 cm error range compounds were analyzed in extracts of two central lines launched in all replicates of the various treatments. For each line, 100 linear meters were measured and quantified the existence of faults; subsequently determined the actual planting observed in each treatment and correlated with output in the treatments. planting lines and identified failures were analyzed through the Geographic Information System (GIS) Quantum Gis. The results of the correlation tended to a positive correlation between the failure data and foliar weight and yield, is a positive indicator of the use of the tool for productivity measurements by the NIR. The studies will be repeated in different conditions and variables for an improvement in productivity analysis and estimationO presente trabalho tem por objetivo estudar o uso de imagens NIR para estimativa de produção de amendoim em três diferentes processos de Plantio (plantio convencional, plantio direto e plantio Rip Strip) relacionando informações de produtividade com parâmetros extraídos de Ortofoto gerada por um Veículo Aéreo Não Tripulado (VANT). As imagens em escala de erro de 0.2 cm foram analisadas em extratos compostos de duas linhas centrais lançados em todas as repetições dos diferentes tratamentos. Para cada linha, com 100 metros lineares foram medidas e quantificadas a existência de falhas; posteriormente determinou-se o efetivo plantio verificado em cada tratamento e correlacionou- se com a produção obtida nos tratamentos. As linhas de plantio e as falhas identificadas, foram analisadas, através do Sistema de Informação Geográfica (SIG) Quantum Gis. Os resultados da correlação tenderam a uma correlação positiva entre os dados de falhas e massa foliar e produtividade, sendo um indicador positivo de uso desta ferramenta para medições de produtividade através de NIR. Os estudos serão repetidos em diferentes condições e variáveis para um aprimoramento da análise e estimativa de produtividade

    Organogenesis and embryogenesis in several hypericum perforatum genotypes

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    St John’s wort (Hypericum perforatum) is a valuable plant used as a herbal remedy or in phytopharmaceutical drugs to treat a variety of physical ailments. Much research has been performed to study the biochemical production of secondary metabolites of in vitro cultured plants or organs. However, all of these studies have looked at the regeneration of plants from explants in only one genotype. In addition, no study has revealed the mechanism of plant regeneration in H. perforatum, i.e. organogenesis or somatic embryogenesis. We found that different genotypes Helos, Topas, Elixir, and Numi responded similarly to regeneration medium. The regeneration responses (i.e. callus, root, or shoot production) of identical explants from different genotypes were similar. However, the source of explant material (leaves, hypocotyls, and roots) from the same genotype had significant effects on the response to media and plant regeneration frequency. Using scanning electron microscopy and light microscopy, the progress of organogenesis and embryogenesis under similar culture conditions was recorded. Root segments were the most responsive explants, producing the maximum number of shoots per explant of all the genotypes.Fundação para a Ciência e a Tecnologia (FCT) - POCTI/AGR/40 283/2001, SFRH/BPD/17102/2004
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