726 research outputs found

    Electronic and magnetic properties of some rare-earth dihydrides and dideuterides

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    Mössbauer spectroscopy has been used to study the electronic and magnetic properties of a number of rare-earth dihydrides and dideuterides. In stoichiometric ErH2 and DyH2, magnetic transitions and crystal field ground states have been established. In non-stoichiometric compounds DyH2+x and (Er)HoH2+x changes of the rare-earth point symmetry due to distributions in hydrogen site occupations are seen. This results in increases in the magnetic transition temperatures and distributions in the magnetic moments

    Age-related differences in motor skill transfer with brief memory reactivation

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    Motor memories can be strengthened through online practice and offline consolidation. Offline consolidation involves the stabilization of memory traces in post-practice periods. Following initial consolidation of a motor memory, subsequent practice of the motor skill can lead to reactivation and reconsolidation of the memory trace. The length of motor memory reactivation may influence motor learning outcomes; for example, brief, as opposed to long, practice of a previously learned motor skill appears to optimize intermanual transfer in healthy young adults. However, the influence of aging on reactivation-based motor learning has been scarcely explored. Here, the effects of brief and long motor memory reactivation schedules on the retention and intermanual transfer of a visuomotor tracing task are explored in healthy older adults. Forty older adults practiced a virtual star-tracing task either three ( brief reactivation ) or ten ( long reactivation ) times per session over a two-week period. Comparison with a previously reported group of younger adults revealed significant age-related differences in the effect of the motor memory reactivation schedule on the intermanual transfer of the motor task. In older adults, unlike younger adults, no significant between-group differences were found by practice condition in the speed, accuracy, or skill of intermanual task transfer. That is, motor task transfer in healthy younger, but not older, adults appears to benefit from brief memory reactivation. These results support the use of age-specific motor training approaches and may inform motor practice scheduling, with possible implications for physical rehabilitation, sport, and music

    Energetic charged particle fluxes relevant to Ganymede's polar region

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    The JEDI instrument made measurements of energetic charged particles near Ganymede during a close encounter with that moon. Here we find ion flux levels are similar close to Ganymede itself but outside its magnetosphere and on near wake and open field lines. But energetic electron flux levels are more than a factor of 2 lower on polar and near-wake field lines than on nearby Jovian field lines at all energies reported here. Flux levels are relevant to the weathering of the surface, particularly processes that affect the distribution of ice, since surface brightness has been linked to the open-closed field line boundary. For this reason, we estimate the sputtering rates expected in the polar regions due to energetic heavy ions. Other rates, such as those related to radiolysis by plasma and particles that can reach the surface, need to be added to complete the picture of charged particle weathering

    Music and dance in respiratory disease management in Uganda: a qualitative study of patient and healthcare professional perspectives

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    Introduction: Music and dance are increasingly used as adjunctive arts-in-health interventions in high-income settings, with a growing body of research suggesting biopsychosocial benefits. Such low-cost, low-resource interventions may have application in low-resource settings such as Uganda. However, research on perceptions of patients and healthcare professionals regarding such approaches is lacking. / Methods: We delivered sample sessions of music and dance for chronic respiratory disease (CRD) to patients and healthcare professionals. Seven participants took part in one singing and dance sample session. One patient completed only the dance session. We then conducted an exploratory qualitative study using thematic analysis of semistructured interviews with healthcare professionals and patients regarding (1) the role of music and dance in Ugandan life and (2) the perceived acceptability and feasibility of using music and dance in CRD management in Uganda. / Results: We interviewed 19 participants, made up of 11 patients with long-term respiratory conditions and 8 healthcare professionals, who were selected by purposeful convenience sampling. Four key themes were identified from interview analysis: music and dance (1) were central components of daily life; (2) had an established role supporting health and well-being; and (3) had strong therapeutic potential in respiratory disease management. The fourth theme was (4) the importance of modulating demographic considerations of culture, religion and age. / Conclusion: Music and dance are central to life in Uganda, with established roles supporting health and well-being. These roles could be built on in the development of music and dance interventions as adjuncts to established components of CRD disease management like pulmonary rehabilitation. Through consideration of key contextual factors and codevelopment and adaptation of interventions, such approaches are likely to be well received

    The Energetic Particle Detector (EPD) Investigation and the Energetic Ion Spectrometer (EIS) for the Magnetospheric Multiscale (MMS) Mission

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    Abstract The Energetic Particle Detector (EPD) Investigation is one of 5 fields-and-particles investigations on the Magnetospheric Multiscale (MMS) mission. MMS comprises 4 spacecraft flying in close formation in highly elliptical, near-Earth-equatorial orbits targeting understanding of the fundamental physics of the important physical process called magnetic reconnection using Earth’s magnetosphere as a plasma laboratory. EPD comprises two sensor types, the Energetic Ion Spectrometer (EIS) with one instrument on each of the 4 spacecraft, and the Fly’s Eye Energetic Particle Spectrometer (FEEPS) with 2 instruments on each of the 4 spacecraft. EIS measures energetic ion energy, angle and elemental compositional distributions from a required low energy limit of 20 keV for protons and 45 keV for oxygen ions, up to \u3e0.5 MeV (with capabilities to measure up to \u3e1 MeV). FEEPS measures instantaneous all sky images of energetic electrons from 25 keV to \u3e0.5 MeV, and also measures total ion energy distributions from 45 keV to \u3e0.5 MeV to be used in conjunction with EIS to measure all sky ion distributions. In this report we describe the EPD investigation and the details of the EIS sensor. Specifically we describe EPD-level science objectives, the science and measurement requirements, and the challenges that the EPD team had in meeting these requirements. Here we also describe the design and operation of the EIS instruments, their calibrated performances, and the EIS in-flight and ground operations. Blake et al. (The Flys Eye Energetic Particle Spectrometer (FEEPS) contribution to the Energetic Particle Detector (EPD) investigation of the Magnetospheric Magnetoscale (MMS) Mission, this issue) describe the design and operation of the FEEPS instruments, their calibrated performances, and the FEEPS in-flight and ground operations. The MMS spacecraft will launch in early 2015, and over its 2-year mission will provide comprehensive measurements of magnetic reconnection at Earth’s magnetopause during the 18 months that comprise orbital phase 1, and magnetic reconnection within Earth’s magnetotail during the about 6 months that comprise orbital phase 2

    The comitology game: European policymaking with parliamentary involvement

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    This paper discusses institutional reforms that might strengthen the role of the European Parliament in the policymaking process of the European Union. Using simple game theory, the paper analyzes the working properties of the different implementation procedures that are known as ‘comitology’. The Council of the European Union employs these procedures when it delegates some of its policymaking power to the Commission as part of Union legislation. We show how the balance of power is determined by the current comitology procedures, and how this balance would change if the role of the European Parliament were strengthened in the comitology game

    Deep learning for automatic target recognition with real and synthetic infrared maritime imagery

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    Supervised deep learning algorithms are re-defining the state-of-the-art for object detection and classification. However, training these algorithms requires extensive datasets that are typically expensive and time-consuming to collect. In the field of defence and security, this can become impractical when data is of a sensitive nature, such as infrared imagery of military vessels. Consequently, algorithm development and training are often conducted in synthetic environments, but this brings into question the generalisability of the solution to real world data. In this paper we investigate training deep learning algorithms for infrared automatic target recognition without using real-world infrared data. A large synthetic dataset of infrared images of maritime vessels in the long wave infrared waveband was generated using target-missile engagement simulation software and ten high-fidelity computer-aided design models. Multiple approaches to training a YOLOv3 architecture were explored and subsequently evaluated using a video sequence of real-world infrared data. Experiments demonstrated that supplementing the training data with a small sample of semi-labelled pseudo-IR imagery caused a marked improvement in performance. Despite the absence of real infrared training data, high average precision and recall scores of 99% and 93% respectively were achieved on our real-world test data. To further the development and benchmarking of automatic target recognition algorithms this paper also contributes our dataset of photo-realistic synthetic infrared images
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