Opportunities and Challenges in Using Learning Analytics in Learning Design

Educational institutions are designing, creating and evaluating courses to optimize learning outcomes for highly diverse student populations. Yet, most of the delivery is still monitored retrospectively with summative evaluation forms. Therefore, improvements to the course design are only implemented at the very end of a course, thus missing to benefit the current cohort. Teachers find it difficult to interpret and plan interventions just-in-time. In this context, Learning Analytics (LA) data streams gathered from ‘authentic’ student learning activities, may provide new opportunities to receive valuable information on the students' learning behaviors and could be utilised to adjust the learning design already "on the fly" during runtime. We presume that Learning Analytics applied within Learning Design (LD) and presented in a learning dashboard provide opportunities that can lead to more personalized learning experiences, if implemented thoughtfully. In this paper, we describe opportunities and challenges for using LA in LD. We identify three key opportunities for using LA in LD: (O1) using on demand indicators for evidence based decisions on learning design; (O2) intervening during the run-time of a course; and, (O3) increasing student learning outcomes and satisfaction. In order to benefit from these opportunities, several challenges have to be overcome. We mapped the identified opportunities and challenges in a conceptual model that considers the interaction of LA in LD.SURF Foundation & NRO under the REFLECTOR project grant

Determination of trace elements in human milk by inductively coupled plasma sectorfield mass spectrometry (ICP-SFMS)

The potential of high resolution inductively coupled plasma sector field mass spectrometry (ICP-SFMS) was evaluated to quantify reliably various toxic and essential elements (Al, Sc, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, As, Ag, Pt, Au, Pb) in human milk and infant formulae with respect to sensitivity, spectral and non-spectral interferences, blank levels, relative stability and accuracy. Some elements of potential interest such as Ti, V, Cr, Mn, Fe, Ni, Co and As are significantly interfered by polyatomic ions and cannot be determined under routine conditions without using high mass resolution, since interference levels vary significantly with the composition of the milk matrix. A microconcentric nebuliser in combination with a membrane desolvation unit was tested with respect to signal enhancement and reduction of interferences. In general, an increase of the signal intensities up to a factor of 5 was observed, whereas not all spectral interferences can be reduced to a negligible amount (only oxide containing ions to some extent). Moreover the use of the N(2) as the make-up gas did not improve the sensitivity but led to additional N-containing polyatomic interferences (e.g., for V, Cr and Mn). The use of a torch shielded by a Pt electrode did lead to the same signal intensities both for the conventional MCN100 and the MCN6000 with membrane desolvation. The investigation of In, Re, Ru, and Rh as internal standard showed that not all elements can be corrected for matrix suppression without using an additional correction factor derived from an approximate matrix composition. A series of milk samples was investigated using the optimised analytical set-up and compared to infant milk formulae. Trace element levels in instant milk formulae are significantly influenced by the quality of tap water used for preparation

The use of X-ray tomography in the study of water repellents and consolidants

To reduce the weathering rate of natural building stones, a wide variety of water repellents and consolidants are commercially available. Although a lot of research is performed on these products, it remains difficult to determine which product is appropriate to use for a certain type of building stone. Each type of building stone has its own petrographic characteristics (mineralogy, texture, ...), leading to typical physical and technical properties which influence its rate of decay. The localisation of the products inside a stone type is not only depending on the properties of the products themselves, but also linked to the texture and structure of the stone. The impregnation depth of the products strongly influences their efficiency and is therefore a key issue in the determination if a product is functional for a certain type of stone. X-ray micro-CT has recently been introduced as a non-destructive material evaluation technique for engineering and geology purposes. The fact that micro-CT can provide information about the internal structure and properties of natural building stones, is a major advantage in the study of their conservation. Firmly linked with more classical research techniques, this non-destructive technique offers an extra dimension to the cultural heritage research. In this paper, non-destructive X-ray computed micro-tomography (micro-CT) turns out to be a powerful tool as it can visualise the presence of water repellents and consolidants inside the stone and can help to detect the influence that these treatments exert on porosity and pore-size distribution. For the visualization of the product its atomic number and density and the amount of product inside the natural building stone is crucial. Besides the contrast in attenuation, the resolution of the micro-CT also needs to be taken into account to obtain a good contrast between stone and product. By doping with 3-bromopropyltrimethoxysilane, more contrast occurs between the stone material and the conservation product. When the amount of product inside the samples is very low and the product is homogeneously spread inside the sample, the doped product is difficult to distinguish from the stone material due to the resolution of the micro-CT. When the amount of doped product inside the stone material reaches a certain threshold value, the dope will appear in the 2D cross-sections derived from micro-CT, creating a good visualization of the products inside the stone samples. (C) 2008 Elsevier B.V. All rights reserved

Dendritic poly-[N-(2-hydroxyethyl)-L-glutamine] as potential drug carrier

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Sensitive assay for midazolam and its metabolite 1'-hydroxymidazolam in human plasma by capillary high-performance liquid chromatography.

A sensitive high-performance liquid chromatographic method is described for the quantification of midazolam and 1'-hydroxymidazolam in human plasma. Sample (1 ml plasma) preparation involved a simple solvent extraction step with a recovery of approximately 90% for both compounds. An aliquot of the dissolved residue was injected onto a 3 microm capillary C18 column (150 mm x 0.8 mm I.D.). A gradient elution was used. The initial mobile phase composition (phosphate buffer-acetonitrile, 65:35) was maintained during 16 min and was then changed linearly during a 1-min period to phosphate buffer-acetonitrile, 40:60. The flow-rate of the mobile phase was 16 microl/min and the eluate was monitored by UV detection. The limits of quantification for midazolam and 1'-hydroxymidazolam were 1 ng/ml and 0.5 ng/ml, respectively. The applicability of the method was demonstrated by studying the pharmacokinetics of midazolam, and its major metabolite 1'-hydroxymidazolam, in human volunteers following i.v. bolus administration of a subtherapeutic midazolam dose (40 microg/kg)