622 research outputs found

    Educational psychology counsellors’ views about children’s participation in educational decision-making: A thematic analysis

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    The attention to children’s participation has increased dramatically during the last decade. Compared to the literature in the educational field, the literature on children’s participation in the social and health fields seems to be developing rapidly. The aim of this article is to address the importance of educational psychology service (eps) counsellors regarding special educational needs (sen) students’ rights to participate in educational decision-making. This article presents an in-depth study of seven Norwegian eps counsellors’ views about children’s participation in educational decision-making. Procedures for a qualitative inductive thematic analysis were followed to reveal four key themes, namely: parents as key persons; children’s presence on teams as an intervention; the importance of children’s age for participation; and the gap between expert assessments and individual education plans (iep s). The results, which are discussed in relation to Lundy’s (2007) model of participation and other relevant literature, show that there should be more knowledge and interventions to ensure children’s participation in educational decision-making in both research and practice. The results also indicate that structures and procedures in special education need to be considered and further developed from a participation perspective.acceptedVersio

    Imaging and manipulation of skyrmion lattice domains in Cu2OSeO3

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    Nanoscale chiral skyrmions in noncentrosymmetric helimagnets are promising binary state variables in high-density, low-energy nonvolatile memory. Skyrmions are ubiquitous as an ordered, single-domain lattice phase, which makes it difficult to write information unless they are spatially broken up into smaller units, each representing a bit. Thus, the formation and manipulation of skyrmion lattice domains is a prerequisite for memory applications. Here, using an imaging technique based on resonant magnetic x-ray diffraction, we demonstrate the mapping and manipulation of skyrmion lattice domains in Cu2OSeO3. The material is particularly interesting for applications owing to its insulating nature, allowing for electric field-driven domain manipulation.Comment: 4 pages, 3 figure

    Magnetic skyrmion interactions in the micromagnetic framework

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    Magnetic skyrmions are localized swirls of magnetization with a non-trivial topological winding number. This winding increases their robustness to superparamagnetism and gives rise to a myriad of novel dynamical properties, making them attractive as next-generation information carriers. Recently the equation of motion for a skyrmion was derived using the approach pioneered by Thiele, allowing for macroscopic skyrmion systems to be modeled efficiently. This powerful technique suffers from the prerequisite that one must have a priori knowledge of the functional form of the interaction between a skyrmion and all other magnetic structures in its environment. Here we attempt to alleviate this problem by providing a simple analytic expression which can generate arbitrary repulsive interaction potentials from the micromagnetic Hamiltonian. We also discuss a toy model of the radial profile of a skyrmion which is accurate for a wide range of material parameters.Comment: 6 pages, 4 figure

    An updated Weichselian chronostratigraphic framework of the Kongsfjorden Trough Mouth Fan and its implications for the glacial history of Svalbard

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    The Arctic is a climate-sensitive area, responding rapidly to present changes, but for the past changes, the record is still incomplete. For instance, the Weichselian glacial history of the Svalbard–Barents Sea Ice Sheet (SBIS) has largely been reconstructed based on studies of the fragmentary Spitsbergen terrestrial and shelf records. However, the sediments removed from the land and shelf areas during peak glacials were deposited on trough mouth fans located along the continental slope. By studying the stratigraphy and processes of the trough mouth fans, comprising a more complete sediment archive, our new data have allowed gaps in the Weichselian glacial history of the SBIS to be refined and filled. Here we present new lithological and geochronological data from the Kongsfjorden Trough Mouth Fan, closely linked to the advance and decay of the SBIS. High-resolution TOPAS seismic profiles reveal three distinct packages of glacigenic debris flows (GDFs) within its upper stratigraphy, each interpreted to represent an advance of the SBIS to the shelf edge. A radiocarbon dated, 12.6-m-long core from the southern flank of the Kongsfjorden Trough Mouth Fan penetrates trough sediments directly linked to the youngest GDF package and terminates in the second GDF, allowing us to study the last two Kongsfjorden ice-stream advances in greater detail than was previously possible. The age model of core GS10-164-09PC, based on combining 14C-, 18O-stable isotope and magnetic susceptibility data, spans the last ~54 ka. An Early Weichselian glacial advance is tentatively dated to have ended at ~90 ka. A second peak glaciation is estimated at ~70 ka, followed by a deglaciation from ~54 ka. An ice rafted debris-rich unit (U7) dated between 38 and 34 ka, followed by a plumite (U6), indicates an advance of unknown extent. The Last Glacial Maximum advance is dated to before 24 ka BP, followed by a rapid deglaciation at ~15 ka. The presence of coarser-grained sorted sediments at the present seafloor is attributed to the influence of the West-Spitsbergen Current, acting on water depths of at least 846 m, and is thought to have worked in the vicinity of the coring site since ~14 ka BP.publishedVersio

    Expanding the Lorentz concept in magnetism

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    This is the final version. Available on open access from IOP Publishing via the DOI in this recordIn 1878, the Dutch physicist Hendrik Antoon Lorentz first addressed the calculation of the local electric field at an atomic site in a ferroelectric material, generated by all the other electric dipoles within the sample. This calculation, which applies equally well to ferromagnets, is taught in Universities around the World. Here we demonstrate that the Lorentz concept can be used to speed up calculations of the local dipolar field in square, circular, and elliptical shaped monolayers and thin films, not only at the center of the film, but across the sample. Calculations show that long elliptical and rectangular films should exhibit the narrowest ferromagnetic resonance (FMR) linewidth. In addition, discrete dipole calculations show that the Lorentz cavity field (μ0M/3)\left({\mu }_{0}M/3\right) does not hold in tetragonal films. Depending on the ratio (b/a), the local field can be either less/greater than (μ0M/3):\left({\mu }_{0}M/3\right): an observation that has implications for FMR. 3D simple cubic (SC) systems are also examined. For example, while most texts discuss the Lorentz cavity field in terms of a Lorentz sphere, the Lorentz cavity field still holds when a Lorentz sphere is replaced by a the Lorentz cube, but only in cubic SC, FCC and BCC systems. Finally, while the primary emphasis is on the discrete dipole–dipole interaction, contact is made with the continuum model. For example, in the continuous SC dipole model, just one monolayer is required to generate the Lorentz cavity field. This is in marked contrast to the discrete dipole model, where a minimum of five adjacent monolayers is required.Engineering and Physical Sciences Research Council (EPSRC

    Ultrahigh magnetic field spectroscopy reveals the band structure of the 3D topological insulator Bi2_2Se3_3

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    We have investigated the band structure at the Γ\Gamma point of the three-dimensional (3D) topological insulator Bi2_2Se3_3 using magneto-spectroscopy over a wide range of energies (0.552.20.55-2.2\,eV) and in ultrahigh magnetic fields up to 150\,T. At such high energies (E>0.6E>0.6\,eV) the parabolic approximation for the massive Dirac fermions breaks down and the Landau level dispersion becomes nonlinear. At even higher energies around 0.99 and 1.6 eV, new additional strong absorptions are observed with a temperature and magnetic-field dependence which suggest that they originate from higher band gaps. Spin orbit splittings for the further lying conduction and valence bands are found to be 0.196 and 0.264 eV

    Reciprocal space mapping of magnetic order in thick epitaxial MnSi films

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    We report grazing incidence small angle neutron scattering (GISANS) and complementary off-specular neutron reflectometry (OSR) of the magnetic order in a single-crystalline epitaxial MnSi film on Si(111) in the thick film limit. Providing a means of direct reciprocal space mapping, GISANS and OSR reveal a magnetic modulation perpendicular to the films under magnetic fields parallel and perpendicular to the film, where additional polarized neutron reflectometry (PNR) and magnetization measurements are in excellent agreement with the literature. Regardless of field orientation, our data does not suggest the presence of more complex spin textures, notably the formation of skyrmions. This observation establishes a distinct difference with bulk samples of MnSi of similar thickness under perpendicular field, in which a skyrmion lattice dominates the phase diagram. Extended x-ray absorption fine structure measurements suggest that small shifts of the Si positions within the unstrained unit cell control the magnetic state, representing the main difference between the films and thin bulk samples

    Contemporary left politics in South Africa: the case of the tri-partite alliance in the Eastern Cape

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    This thesis aims to make sense of Left politics in South Africa within the Tri-partite Alliance between the ANC, SACP and COSATU. The thesis focuses on developments in the Eastern Cape, between 2000 and 2008. The thesis describes the prevalent forms of Left politics in the Eastern Cape and the tendencies in the Alliance that organise this Left. The thesis also examines the historical, social and political conditions and that shape the form and content of Left politics in the province. Based on a survey of literature on what is considered the core manifestations of Left politics globally in the 20th Century Left politics is defined as the elements of the political spectrum that are concerned with the progressive resolution of involuntary disadvantage and with a goal of abolishing class society and capitalism. Although the Alliance as a whole should be seen to be on the Left on an international political spectrum, this thesis argues that the Left/Right dichotomy is useful for understanding the politics of the Alliance, as long as the second part of this definition is taken into consideration. The Alliance Left is understood as those leaders and activists within the Alliance that have the SACP and Cosatu as their operating base. It will be argued that this Left is, in its practice, largely concerned with what insiders refer to as politics of „influence‟, rather than with politics of „structural transformation‟. It is the ANC that is the leader of the Alliance and the party in government and thus it is on the terrain of ANC strategy, policy and positions that contestation in the Alliance plays itself out. Thus, for the Left, there is strength in the idea of the Alliance. However, there are significant theoretical and political weaknesses in the Left that undermine the possibility of making good use of various corporatist platforms to pursue the agenda of the Left in the Eastern Cape. There is also increased contestation within the Alliance Left itself about the continued usefulness of this strategy

    Transforming Scientists’ Understanding of Science–Society Relations. Stimulating Double‑Loop Learning when Teaching RRI

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    The problem of developing research and innovation in accordance with society’s general needs and values has received increasing attention in research policy. In the last 7 years, the concept of “Responsible Research and Innovation” (RRI) has gained prominence in this regard, along with the resulting question of how best to integrate awareness about science–society relations into daily practices in research and higher education. In this context, post-graduate training has been seen as a promising entrance point, but tool-kit approaches more frequently have been used. In this paper, we present and analyze an experiment—in the format of a Ph.D. course for early-career researchers—deploying an alternative approach. Drawing on Argyris and Schön’s (1974) framing of reflective practice, and their distinctions between espoused theories and theories-in-use, the analyzed course endeavored to stimulate double-loop learning. Focusing on dislocatory moments, this paper analyses how the course tried to teach participants to reflect upon their own practices, values, and ontologies, and whether this provided them with the resources necessary to reflect on their theories-in-use in their daily practices.publishedVersio
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