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Background: The large-scale International Computer and Information Literacy Study (2018) has an interesting finding concerning Luxembourg teachers. Luxembourg has one of the highest reported level of technology-related resources for teaching and learning, but a relatively lower reported use of ICT in classroom practice. Methods: ICT innovation requires a high initial level of financial investment in technology, and Luxembourg has achieved this since 2015. Once the necessary financial investment in ICT technology has been made, the key question is what else matters to increase the use of ICT in teaching. To identify the relevant factors, we used the "Four in Balance" model, aimed explicitly at monitoring the implementation of ICT in schools. Results: Using data for 420 teachers in Luxembourg, we identify that within such a technology-driven approach to digitalization, teachers' vision of ICT use in teaching, level of expertise, and the use of digital learning materials in class are significant support factors. Leadership and collaboration, in the form of an explicit vision of setting ICT as a priority for teaching in the school, also prove to be important. Conclusions: Through these findings, we show that the initial investment in school infrastructure for ICT needs to be associated in its implementation with teachers' ICT-related beliefs, attitudes, and ICT expertise. [ABSTRACT FROM AUTHOR]

The permeability of metallic and ceramic open-cell foams prepared by the gelcasting technique was assessed by fitting of Forchheimer’s equation to experimental pressure drop curves. The ceramic composition was based on pure hydroxyapatite, while the metallic composition was based on titanium metal. Experimental Darcian ( k) and non-Darcian ( k) permeability constants displayed values in the range 0.40–3.24 × 10 m and 3.11–175.8 × 10 m respectively. Tortuosity was evaluated by gas diffusion experiments and ranged from 1.67 to 3.60, with porosity between 72 and 81% and average hydraulic pore size between 325 and 473 μm. Such features were compared to data reported in the literature for cancellous bones and synthetic scaffolds for bone graft. A detailed discussion concerning the limitations of Darcy’s law for fitting laboratory data and for predicting fluid flow through scaffolds in real biomedical applications is also performed. Pore size was obtained by image analysis and was also derived from permeation-absorption-diffusion experiments. In both cases, values were within the range expected for porous scaffolds applications. [ABSTRACT FROM AUTHOR]

With the aim to understand and estimate the economic impact of outbreaks of community-acquired infections, we performed a review focusing on hepatitis A outbreaks, and retained 13 papers that had collected relevant cost information during such outbreaks. All costs in this article are expressed in USD, year 2007 values. The costs of hepatitis A outbreaks ranged from USD140 000 to US36 million, and the costs per case in an outbreak situation ranged from USD3824 to USD200 480. These costs were typically found to be substantially higher than estimates from cost-of-illness studies (i.e. costs for sporadic cases) and estimates used in cost-effectiveness analyses, mostly because of costly outbreak-control measures. Post-exposure prophylaxis is a major cost factor, especially for food-borne outbreaks. As a result of the increasing proportion of those susceptible to hepatitis A in low-incidence countries, future outbreaks could, on average, increase in size. The increasing occurrence of hepatitis A cases in outbreak situations and the associated control costs should appropriately be accounted for in economic evaluations of vaccination programmes in low-incidence countries. In order to do this, more studies documenting such outbreak-control strategies in terms of costs and resource use are needed. [ABSTRACT FROM AUTHOR]

The effect of non-Faradaic electrochemical modification of catalytic activity (NEMCA) was investigated for the case of CH oxidation on a Pt polycrystalline catalyst film also acting as a working electrode in a galvanic cell of the type: In addition to proton conduction, CaZrInO is known to exhibit oxygen and hole conduction. Proton conduction predominates over the temperature range, 380 to 460 °C, of the present investigation. It was found that negative current application, i.e. proton supply to the Pt catalyst film causes up to 500% reversible enhancement to the rate of CH oxidation. The catalytic rate increase is up to 20,000 higher than the rate, -I/F, of proton supply to the catalyst. The observed phenomena are discussed within the framework of previous electrochemical promotion (NEMCA) studies. [ABSTRACT FROM AUTHOR]

Magnesium sensitive probes were constructed and tested in different melts of commercial aluminium-magnesium alloys. The probes were composed of a porous magnesium oxide one closed end tube or thimble to which a magnesium conducting salt is impregnated. The activity of magnesium in the aluminium-magnesium melt was determined with report to a pure magnesium reference contained in the inside of the thimble and sealed from the surrounding atmosphere and melt by zirconia based cement. Measurements were conducted in various commercial aluminium-magnesium alloys under inert atmosphere as well as in air. [ABSTRACT FROM AUTHOR]

The preparation and characterization of porous ceramic membranes is presented. These membranes consist of a macroporous support system, with or without a mesoporous intermediate layer, and a microporous top layer. For the macroporous support membranes two manufacturing routes are described: a conventional and a RBAO (Reaction Bonded Aluminium Oxide) route. The mesoporous γ-Al2O3 layer is obtained by means of a sol-gel dipcoating technique. Three microporous top layers are considered: SiO2, Al2O3-pillared montmorillonite and Laponite. These top layers have different pore structures which results in different gas transport properties. A SiO2 membrane can be used for H2 removal from a gas mixture. Al2O3-pillared montmorillonite and Laponite membranes do not show specific gas separation properties. Dehydration of water/2-propanol mixtures by means of pervaporation also proved a different behavior for these microporous membranes. [ABSTRACT FROM AUTHOR]

In the eighties, Iwahara discovered that doped Sr and Ba cerates show significant proton conduction, at high temperature, and in hydrogen- or water-containing atmosphere [1]. Begin '90 it was proved that also doped zirconates (Sr, Ba, Ca) join this family of proton conducting perovskites [2]. Within this group, indium doped CaZrO is one of the more interesting materials for applications, being mechanically and chemically particularly stable, and producible in very dense form. Specifically, it was already succesfully incorporated in a hydrogen sensor for liquid aluminium [3]. In principle, this sensor works as a simple electrochemical hydrogen concentration cell described by Nernst. However, as already remarked phenomenologically from the beginning [1], a hydrogen concentration cell using these perovskites shows the theoretically predicted emf, only in the presence of humidity. In this paper we want to go deeper into the reasons for this phenomenon. [ABSTRACT FROM AUTHOR]

We report a new mutation in the sterol 27-hydroxylase (CYP 27) gene in a Dutch family with cerebrotendinous xanthomatosis: a G→A transition in the splice donor site in intron 4. This mutation leads to skipping of exon 4, resulting in a loss of 66 amino acids in the CYP 27 enzyme molecule. [ABSTRACT FROM AUTHOR]

This report concerns two new mutations in the sterol 27-hydroxylase gene in two patients with cerebrotendinous xanthomatosis (CTX). In a Surinam-Creole patient (patient A), a G deletion on position cDNA 546/547 in exon 3 led to a frameshift and the introduction of a premature termination codon. In a Dutch patient (patient B), a C→T transition at position 496 in exon 3 also led to a premature termination codon. Patient A was homozygous for the mutation, whereas patient B was compound heterozygous, a C→T transition also being found in exon 6 at position 1204. The two new mutations were confirmed by restriction analysis with the restriction enzymes FokI and MaeI, respectively. [ABSTRACT FROM AUTHOR]