11,447 research outputs found
Semantic modelling of learning objects and instruction
We introduce an ontology-based semantic modelling framework that addresses subject domain modelling, instruction modelling, and interoperability aspects in the development of complex reusable learning objects. Ontologies are knowledge representation frameworks, ideally suited to support knowledge-based modelling of these learning objects. We illustrate the benefits of semantic modelling for learning object assemblies within the context of standards such as SCORM Sequencing and Navigation and Learning Object Metadata
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Replicating the Family: The Biopolitics of Involvement Discourses Concerning Relatives in Nursing Home Institutions
The aim of this study was to describe the biopolitics of involvement discourses articulated by nursing staff concerning relatives in nursing home institutions, using a Foucault-inspired discourse analytical approach. Previous research has described how relatives have not been involved in nursing homes on their own terms. This is partly due to a lack of communication and knowledge, but it is also a consequence of an unclear organizational structure. Results from a discourse analysis of six focus group interviews with nursing staff show that the “involvement discourse” in nursing homes can be described as a “new” vs “old” family rhetoric. This rhetoric can be said to uphold, legitimize and provide different subject positions for both nursing staff and relatives concerning the conditions for involvement in nursing homes. As part of a “project of possibility” in elderly care, it may be possible to adopt a critical pedagogical approach among nursing staff in order to educate, strengthen and support them in reflecting on their professional norming and how it conditions the involvement of relatives
Finite-size versus Surface effects in nanoparticles
We study the finite-size and surface effects on the thermal and spatial
behaviors of the magnetisation of a small magnetic particle. We consider two
systems: 1) A box-shaped isotropic particle of simple cubic structure with
either periodic or free boundary conditions. This case is treated analytically
using the isotropic model of D-component spin vectors in the limit , including the magnetic field. 2) A more realistic particle (-FeO) of ellipsoidal (or spherical) shape with open boundaries.
The magnetic state in this particle is described by the anisotropic classical
Dirac-Heisenberg model including exchange and dipolar interactions, and bulk
and surface anisotropy. This case is dealt with by the classical Monte Carlo
technique. It is shown that in both systems finite-size effects yield a
positive contribution to the magnetisation while surface effects render a
larger and negative contribution, leading to a net decrease of the
magnetisation of the small particle with respect to the bulk system. In the
system 2) the difference between the two contributions is enhanced by surface
anisotropy. The latter also leads to non saturation of the magnetisation at low
temperatures, showing that the magnetic order in the core of the particle is
perturbed by the magnetic disorder on the surface. This is confirmed by the
profile of the magnetisation.Comment: 6 pages of RevTex including 4 Figures, invited paper to 3rd
EuroConference on Magnetic Properties of Fine Nanoparticles, Barcelona,
October 9
Presence and fate of priority substances in domestic greywater treatment and reuse systems
A wide range of household sources may potentially contribute to contaminant loads in domestic greywater. The ability of greywater treatment systems to act as emission control barriers for household micropollutants, thereby providing environmental benefits in addition to potable water savings, have not been fully explored. This paper investigates the sources, presence and potential fate of a selection of xenobiotic micropollutants in on-site greywater treatment systems. All of the investigated compounds are listed under the European Water Framework Directive as either "Priority Substances" (PS) or "Priority Hazardous Substances" (PHS). Significant knowledge gaps are identified. A wide range of potential treatment trains are available for greywater treatment and reuse but treatment efficiency data for priority substances and other micropollutants is very limited. Geochemical modelling indicates that PS/PHS removal during treatment is likely to be predominantly due to sludge/solid phase adsorption, with only minor contributions to the water phase. Many PS/PHS are resistant to biodegradation and as the majority of automated greywater treatment plants periodically discharge sludge to the municipal sewerage system, greywater treatment is unlikely to act as a comprehensive PS/PHS emission barrier. Hence, it is important to ensure that other source control options (e.g. eco-labeling, substance substitution, and regulatory controls) for household items continue to be pursued, in order that PS/PHS emissions from these sources are effectively reduced and/or phased out as required under the demands of the European Water Framework Directive
Coherent States with SU(N) Charges
We define coherent states carrying SU(N) charges by exploiting generalized
Schwinger boson representation of SU(N) Lie algebra. These coherent states are
defined on complex planes. They satisfy continuity property
and provide resolution of identity. We also exploit this technique to construct
the corresponding non-linear SU(N) coherent states.Comment: 18 pages, LaTex, no figure
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Predictive markers for humoral influenza vaccine response in patients with common variable immunodeficiency (CVID)
BACKGROUND: A subgroup of patients with common variable immunodeficiencies (CVID) responds to vaccination. The aim of the study was to try to identify predictive markers for those who developed a humoral immune response after influenza vaccination. METHODS: 48 patients with CVID (29 females, 19 males, mean age 59.4 years) were vaccinated with the A(H1N1) influenza vaccine Pandemrix® and boosted after one month. Blood samples were collected prior to each vaccination and two months later. Patients with a 4-fold titer increase of the hemagglutinin inhibition test (≥ 1:40) were considered responders and compared to non-responders for clinical, immunological and genetic markers. RESULTS: Eight (16.7%) patients responded to the vaccination. A significantly higher proportion of the responders, who showed a Euroclass SmB-Trnorm21norm profile (p=0.03) with a post-germinal center B cell pattern (p=0.04) in blood, suffered from enteropathies (p=0.04) as compared to non-responders. Bronchiectasis on the other hand, was exclusively found among non-responders (n=7), as was autoimmune cytopenia (n=5). Non-responders with a Euroclass SmB-21lowTrnorm profile (p=0.02), had a significantly higher prevalence of progressive antibody deficiency (p=0.048) and, at diagnosis, a higher mean serum IgM level (p=0.03), a lower mean serum IgG1 level (p=0.007), an expansion of absolute counts of cytotoxic CD8+ T-cells (p=0.033) and an increased proportion of memory CD8+ T-cells (p=0.044) in blood. CVID associated HLA markers were not detected in non-responders (p=0.03). CONCLUSION: About one-fifth of the CVID patients achieved protective antibody levels after A(H1N1) vaccination and selected clinical and immunological markers were identified that may predict a positive outcome of influenza vaccination
Centrifugal acceleration in the magnetotail lobes
Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few <I>R</I><sub>E</sub>. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s<sup>&minus;2</sup>. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 <I>R</I><sub>E</sub> geocentric distance is less than 5 km s<sup>&minus;1</sup>
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