76 research outputs found

    Extended matching sets questions for numeracy assessments

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    Extended matching sets questions (EMSQs) are a form of multiple choice question (MCQ) consisting of a stem (the question or scenario) followed by an extended number of possible answers (Wilson & Case, 1993). An EMSQ is defined here as a question with ten or more alternative answers. EMSQs have been most frequently applied to medical education (Case and Swanson, 1994; Alcolado and Mir, 2002), but can also play a valuable role in assessment of numeracy

    Reflection on-line or off-line: the role of learning technologies in encouraging students to reflect

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    This paper presents case studies that describe the experiences of the two authors in trying to use learning technologies to facilitate reflective thinking in their students. At the University of Leicester, a Web-based biology tutorial called ‘How Now Mad Cow’, which covers the topics of bovine spongiform encephalopathy and a new variant Creutzfeldt–Jakob disease (nvCJD). At the University of Southampton, a web-based hyper-mail discussion list to support teaching on a first year psychosocial science module for occupational therapy and physiotherapy students has been established. In both examples, the tutors had attempted to create a learning environment that would engage students in the learning experience and facilitate reflection by helping them to create meaning from the learning experience and see things in a different way. The evaluation data from both case studies provides some evidence that the learning technologies helped to facilitate reflection for some students. However, the evidence for reflection is not overwhelming and the data provides some evidence that four key factors may have influenced how successful the use of learning technologies were in facilitating reflection. These factors are the way the learning technology is used, the nature of the student groups, the role of the tutor and student preferences for ‘off-line reflection’. These are discussed and ways forward are identified

    Finite-size scaling in silver nanowire films: design considerations for practical devices

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    We report the first application of finite-size scaling theory to nanostructured percolating networks, using silver nanowire (AgNW) films as a model system for experiment and simulation. AgNWs have been shown to be a prime candidate for replacing Indium Tin Oxide (ITO) in applications such as capacitive touch sensing. While their performance as large area films is well-studied, the production of working devices involves patterning of the films to produce isolated electrode structures, which exhibit finite-size scaling when these features are sufficiently small. We demonstrate a generalised method for understanding this behaviour in practical rod percolation systems, such as AgNW films, and study the effect of systematic variation of the length distribution of the percolating material. We derive a design rule for the minimum viable feature size in a device pattern, relating it to parameters which can be derived from a transmittance-sheet resistance data series for the material in question. This understanding has direct implications for the industrial adoption of silver nanowire electrodes in applications where small features are required including single-layer capacitive touch sensors, LCD and OLED display panels

    Carbon nanofoam supercapacitor electrodes with enhanced performance using a water-transfer process

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    Carbon nanofoam (CNF) is a highly porous,amorphous carbon nanomaterial that can be produced through the interaction of a high-fluence laser and a carbon-based target material. The morphology and electrical properties of CNF make it an ideal candidate for super-capacitor applications. In this paper, we prepare and characterize CNF supercapacitor electrodes through two different processes, namely, a direct process and a water-transfer process. We elucidate the influence of the production process on the microstructural properties of the CNF, as well as the final electrochemical performance. We show that a change in morphology due to capillary forces doubles the specific capacitance of the wet-transferred CNF electrodes

    Graphene-based printable conductors for cyclable strain sensors on elastomeric substrates

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    Printable stretchable devices, which can be used in a wide range of environments, are required for a range of flexible or stretchable electronics applications. Here we present an ink containing liquid exfoliated graphene and natural rubber, which can be printed onto a variety of elastomeric substrates and recover conductance after multiple strains of up to 15%. In addition, the printed composite acts as a strain sensor with a gauge factor of around 7. The robust character of these composites allows for operation at temperatures up to 150 °C. The combination of the effectiveness of the device, along with comparable performance at elevated temperatures while being relatively cheap makes this ideal for integration with automotive components. For applications that require superior conductivity, silver nanowires can be added. The enhanced conductivity composite cannot withstand higher temperatures due to the breakdown of the nanowires. However, at room temperature the material shows similar recovery of conductivity after cycling leading to a highly conductive, room temperature, printable, stretchable composite

    Self-directed behavioral family intervention: Do therapists matter?

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    Behavioral family intervention is an effective form of intervention for the prevention and treatment of a wide range of emotional and behavioral problems in children. There is a growing need to address the accessibility of these services. This paper reviews the literature on self-directed interventions designed to help parents manage difficult child behaviors. Evidence regarding the efficacy of interventions is reviewed, and some of the difficulties associated with self-directed programs are discussed. The Self-directed Triple P and Teen Triple P-Positive Parenting Programs are highlighted as examples of efficacious and effective behavioral family interventions fitting into a larger multi-level model of family intervention. The discussion of the efficacy and effectiveness of self-directed Triple P has implications for service delivery of parenting programs

    Iron-catalysed, general and operationally simple formal hydrogenation using Fe(OTf)(3) and NaBH4

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    An operationally simple and environmentally benign formal hydrogenation protocol has been developed using highly abundant iron(iii) salts and an inexpensive, bench stable, stoichiometric reductant, NaBH(4), in ethanol, under ambient conditions. This reaction has been applied to the reduction of terminal alkenes (22 examples, up to 95% yield) and nitro-groups (26 examples, up to 95% yield). Deuterium labelling studies indicate that this reaction proceeds via an ionic rather than radical mechanism

    AI is a viable alternative to high throughput screening: a 318-target study

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    : High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery
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