18 research outputs found

    Task complexity, age and gender effect on functional motor asymmetry of right- and left-handed children

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    Manual asymmetry was assessed in different complexity coincidence-anticipation tasks in 59 right- and 56 left-handed children of both genders divided into two age groups (7-8 years and 9-10 years). Results revealed that (i) manual asymmetry increased with task complexity in both handedness groups without reaching statistical significance for the left-handed group; (ii) for the left-handed group, manual asymmetry was evident in all measured errors; (iii) better performance was presented when executing simpler tasks for both handedness groups; (iv) maturational effect was more pronounced in the complex task; (v) in both handedness groups, the 9-10-year-old group was more accurate and less variable when compared to the 7-8 year-old group; (vi) interaction between age and task complexity revealed that males outperformed females in both handedness. These results favor the perspective in which handedness is seen as a dynamic process, where motor preference interacts with task complexity

    Modelos acoplados do IPCC-AR4 e o gradiente meridional de temperatua da superficie do mar no atlântico tropical : relaçoes com a precipitaçao no norte do nordeste do Brasil

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    Este artigo mostra como três modelos acoplados do Intergovernmental on Panel Climate Change - (IPCC-AR4), o FGOALS1. 0G – LASG do Institute of Atmospheric Physics of China, o GISSER da National Aeronautics Space Admnistration (NASA) e o GFDL_CM2 da National Oceanic and Atmospheric Administration (NOAA), simularam a variabilidade do gradiente meridional de Temperatura da Superfície do Mar (TSM), entre os meses de fevereiro a maio, no Atlântico Tropical (1901-1999). A precipitação durante a estação chuvosa (fevereiro a maio) no setor norte do Nordeste do Brasil (NEB) foi também analisada pelos três modelos e comparada com as observações. Os modelos GISSER e FGOALS1.0G mostraram melhor desempenho na simulação do sinal do gradiente meridional de TSM no Atlântico Tropical para o período de 1901 a 1999. Destaca-se que os modelos apresentaram um melhor desempenho na simulação da tendência decadal, conseguindo explicar entre 50% a 80% da variabilidade do gradiente, com a TSM do setor sul sendo mais bem simulada

    Historical separation and present-day structure of common dolphinfish (Coryphaena hippurus) populations in the Atlantic Ocean and Mediterranean Sea

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    The common dolphinfish (Coryphaena hippurus) is an epipelagic, mid-trophic level, highly migratory species distributed throughout the world’s tropical and subtropical oceans in waters greater than 20C. Life-history variables, migratory behaviour, and genetic markers have been used to define major stocks in the central Atlantic Ocean and Mediterranean Sea. Here, we used the mitochondrial DNA gene NADH subunit 1 (688 bp) to test for differences between population groups. A total of 103 haplotypes were detected among 203 fish. Gene diversities in samples were large and similar among populations (mean h ¼ 0.932; range 0.894–0.987), but nucleotide diversities varied widely among samples (range p ¼ 0.004–0.034) and appear to reflect population histories. Principal component analysis revealed two large populations groups, and the analysis of molecular variation and pairwise values of UST resolved population structure within these groups. Populations in the eastern Atlantic and Mediterranean showed the largest amounts of divergence from one another (UCT ¼ 0.331). Adult movement and biophysical barriers to larval dispersal may explain contemporary differences between stocks, but the divergent populations in the Mediterranean Sea are likely due to isolations by cold temperature barriers during Pleistocene glaciations. The geographically large stock groupings require international cooperation in the harvest management and conservation of local dolphinfish populations

    Quantum gravity phenomenology at the dawn of the multi-messenger era—A review

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    The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.publishedVersio

    Functional Definition of the INFOGENMED WORKSTATION: A Virtual Laboratory for Genetic Information Management in Clinical Environments

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    New technologies (biochips, bioinformatics) and research approaches (Proteomics, Funtional Genomics, Individual Genomics) are revolutionising biomedical research. The Human Genome Project is making a major contribution to the knowledge of the relationships between human genes and physiopathological states. There are already 4500 genes associated with illnesses in the OMIM database. The integration of these massive amounts of genetic information in the clinical environment will give rise to a new clinical practice based on Molecular Medicine. Diagnosis will be more precise and include genetic tests that may be done at the point of care using biochip technology. Therapies will include personalised drugs that will have molecular targets

    Surface modification of stainless steel powders for microfabrication

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    The current trend towards miniaturization has led to the increasing use of stainless steel powders as raw material in the manufacture small parts with complex shapes, e.g. medical devices. This paper focuses on the role of coated and uncoated low carbon stainless steel powders, having d50 = 7.3 [mu]m, normal particle size distribution and a shape factor of 1 on additive processes used in micromanufacturing, e.g. micro powder injection moulding ([mu]PIM). Surfaces were treated using a magnetron sputtering deposition apparatus equipped with a high frequency powder vibration and a continuous feed system. The results clearly show that the coated powders assume an "artichoke" morphology, which significantly increases the surface area. This combined with their nanocrystalline character leads to higher flowability than uncoated powders. However, no improvements have been observed concerning the critical powder volume concentration (CPVC) in feedstocks for [mu]PIM processing. In consolidation processes, the debinding temperatures can attain values higher than 500 °C. After debinding and sintering, the coating of steel powders can show lower carbon contamination in solid solution than uncoated ones. This result is very important particularly for powder microtechnology of low carbon stainless steel.http://www.sciencedirect.com/science/article/B6TGJ-4R7J837-19/1/c3ced7613d4cb2b5e4de14f154d7f51
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