148 research outputs found

    Experimental creep behaviour determination of cladding tube materials under multi-axial loadings

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    Cladding tubes are structural parts of nuclear plants, submitted to complex thermomechanical loadings. Thus, it is necessary to know and predict their behaviour to preserve their integrity and to enhance their lifetime. Therefore, a new experimental device has been developed to control the load path under multi-axial load conditions. The apparatus is designed to determine the thermomechanical behaviour of zirconium alloys used for cladding tubes. First results are presented. Creep tests with different biaxial loadings were performed. Results are analysed in terms of thermal expansion and of creep strain. The anisotropy of the material is revealed and iso-creep strain curves are given

    Effect of Feedback on Performance in the Lane-Change Test

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    The Lane-Change Test (LCT) is an easy-to-use methodological tool that has proven useful for researching dual-task driving situations. This paper examines the effect of feedback on LCT performance. Feedback is important for maintaining the focus of attention on the primary (driving) task and providing motivation for learning. An experiment was conducted in which two driver groups performed the LCT with or without end-of-block summary feedback. Results showed that the presence of feedback significantly improved performance, as revealed by lower overall means and lower standard deviations (with practice) of lateral deviation values. We conclude that feedback can have a positive effect on performance in the LCT and, therefore, it may be critical to include such feedback when using this, as well as similar tasks, to investigate dual-task driving situations

    Indexing grey multilingual literature in General Practice: Family medicine in the era of semantic web

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    peer reviewedProblem/Goal: Sharing the results of research with General Practitioners (GPs) is crucial for the survival of the discipline of General Practice / Family Medicine (GP/FM). The production of abstracts in GP/FM probably exceeds 15,000 per year worldwide. Each abstract often represents two years of work for its authors and is expressed in local languages. Only 45% of them are published in indexed medical journals. Usual indexing systems like MeSH are not multilingual nor adapted to the particular field of GP/FM. Consequently, these abstracts are lacking bibliographic control and more than half of the research presented by GPs at congresses is lost. Considering the absence of appropriate domain-specific terminologies or classification systems, we propose a new multilingual indexing system. The existing International Classification of Primary Care (ICPC) is currently used for clinical purposes and has now been expanded with a taxonomy related to contextual aspects (called Q-Codes) such as education, research, practice organization, ethics or policy in GP/FM, currently not captured. The set is proposed under the name Core Content Classification in General Practice (3CGP). The aim is to facilitate indexing of GP/FM specific scientific work and to improve performance in information storage and retrieval for research purposes in this field. Research Method/Procedure: Using qualitative analysis, a corpus of 1,702 abstracts from six GP/FM- related European congresses was analyzed to identify main themes discussed by GPs (e.g., continuity, accessibility or medical ethics), handled in a domain-specific taxonomy called Q-Codes and translated in 8 languages. In addition, a methodology for building a lightweight ontology (in OWL-2) was applied to Q-Codes, adding object and datatype properties to the hierarchical relations, including mapping to the MeSH thesaurus, Babelnet (www.babelnet.org) and Dbpedia. Finally, the Q-Codes in 8 languages have been integrated healthcare terminology service (www.hetop.eu/q) with a companion website (http://3cgp.docpatient.net). Anticipated Results of the Research: The creation and the on-line publication of this multilingual terminological resource, for indexing abstracts and for facilitating Medline searches, could reduce loss of knowledge in the domain. In addition, through better indexing of the grey literature (congress abstracts, master’s and doctoral thesis), we hope to enhance the accessibility of research results of GP/FM domain and promote the emergence of networks of researchers. First result of experimental implementations of the new indexing system will be presented. Indication of costs related to the project: This project has not been funded. 3CGP is placed under Attribution-Non-Commercial-Share-Alike 4.0 International (CC BY-NC-SA 4.0). ICPC is copyrighted by WONCA. © 2018 Oriental Scientific Publishing Company. All rights reserved

    Intervenir sur les souffrances au travail : acteurs et enjeux dans la durĂŠe

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    National audience[début du texte] La santé psychique au travail fait l’objet, depuis plusieurs années, de débats entre chercheurs, porteurs de théories sensiblement différentes, au sein de la psychologie du travail. D’une part, des études à l’échelle de l’organisation essaient de caractériser et d’expliquer, à partir de données quantitatives, les facteurs qui conduisent à différentes formes de souffrance chez les travailleurs (stress, anxiété, épression, suicide)

    Bisphosphonates reduce biomaterial turnover in healing of critical-size rat femoral defects.

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    Treatment of osteoporotic patients with bisphosphonates (BPs) preserves bone mass and microarchitecture. The high prescription rate of the drugs brings about increases in the numbers of fractures and bone defects requiring surgical interventions in these patients. Currently, critical-size defects are filled with biomaterials and healing is supported with bone morphogenetic proteins (BMP). It is hypothesized that BPs interfere with biomaterial turnover during BMP-supported repair of defects filled with β-tricalcium phosphate (βTCP) ceramics. To test this hypothesis, retired breeder rats were ovariectomized ( OVX). After 8 weeks, treatment with alendronate (ALN) commenced. Five weeks later, 6 mm diaphyseal femoral defects were applied and stabilized with locking plates. βTCP cylinders loaded with 1 Οg and 10 Οg BMP2, 10 Οg L51P, an inhibitor of BMP antagonists and 1 Οg BMP2/10 Οg L51P were fitted into the defects. Femora were collected 16 weeks post-implantation. In groups receiving calcium phosphate implants loaded with 10 Οg BMP2 and 1 Οg BMP2/10 Οg L51P, the volume of bone was increased and βTCP was decreased compared to groups receiving implants with 1 Οg BMP2 and 10 Οg L51P. Treatment of animals with ALN caused a decrease in βTCP turnover. The results corroborate the synergistic effects of BMP2 and L51P on bone augmentation. Administration of ALN caused a reduction in implant turnover, demonstrating the dependence of βTCP removal on osteoclast activity, rather than on chemical solubility. Based on these data, it is suggested that in patients treated with BPs, healing of biomaterial-filled bone defects may be impaired because of the failure to remove the implant and its replacement by authentic bone

    Acting while perceiving: assimilation precedes contrast

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    To explore the nature of specific interactions between concurrent perception and action, participants were asked to move one of their hands in a certain direction while simultaneously observing an independent stimulus motion of a (dis)similar direction. The kinematics of the hand trajectories revealed a form of contrast effect (CE) in that the produced directions were biased away from the perceived directions (“Experiment 1”). Specifically, the endpoints of horizontal movements were lower when having watched an upward as opposed to a downward motion. However, when participants moved under higher speed constraints and were not presented with the stimulus motion prior to initiating their movements, the CE was preceded by an assimilation effect, i.e., movements were biased toward the stimulus motion directions (“Experiment 2”). These findings extend those of related studies by showing that CEs of this type actually correspond to the second phase of a bi-phasic pattern of specific perception–action interference

    The role of motor simulation in action perception: a neuropsychological case study

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    Research on embodied cognition stresses that bodily and motor processes constrain how we perceive others. Regarding action perception the most prominent hypothesis is that observed actions are matched to the observer’s own motor representations. Previous findings demonstrate that the motor laws that constrain one’s performance also constrain one’s perception of others’ actions. The present neuropsychological case study asked whether neurological impairments affect a person’s performance and action perception in the same way. The results showed that patient DS, who suffers from a frontal brain lesion, not only ignored target size when performing movements but also when asked to judge whether others can perform the same movements. In other words DS showed the same violation of Fitts’s law when performing and observing actions. These results further support the assumption of close perception action links and the assumption that these links recruit predictive mechanisms residing in the motor system

    On interference effects in concurrent perception and action

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    Recent studies have reported repulsion effects between the perception of visual motion and the concurrent production of hand movements. Two models, based on the notions of common coding and internal forward modeling, have been proposed to account for these phenomena. They predict that the size of the effects in perception and action should be monotonically related and vary with the amount of similarity between what is produced and perceived. These predictions were tested in four experiments in which participants were asked to make hand movements in certain directions while simultaneously encoding the direction of an independent stimulus motion. As expected, perceived directions were repelled by produced directions, and produced directions were repelled by perceived directions. However, contrary to the models, the size of the effects in perception and action did not covary, nor did they depend (as predicted) on the amount of perception–action similarity. We propose that such interactions are mediated by the activation of categorical representations
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