33 research outputs found

    Understanding dental students’ use of feedback

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    Introduction Feedback can enhance learning and is thought to be highly valued by students; however, it is not clear from the literature how dental students actually use feedback. Aim This study aimed to explore how dental students use feedback in a variety of contexts. Methods Qualitative methods involving audio‐recorded focus groups were used to explore the use of feedback by undergraduate dental students studying at three UK dental schools. A purposive sampling strategy was used to ensure diverse representation across the undergraduate dental programmes in each of the schools. Results Six focus groups, involving a total of 72 students, were undertaken. Thematic analysis identified five main themes relating to the use of feedback: value, future applicability, accessibility, variability and understanding. The inter‐connectivity and interaction of the themes (along with their subthemes) were used to develop a model for optimising feedback with the aim of enhancing its potential use by students. Conclusion The use of feedback by students would appear to be strongly influenced by several factors. Understanding these factors and how they interlink may be helpful to education providers who are seeking to optimise their feedback processes

    Phase Stability and Electronic Properties of Hybrid Organic–Inorganic Perovskite Solid Solution (CH(NH2)2)x(CH3NH3)1–xPb(BryI1–y)3 as a Function of Composition

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    Compositional mixing provides the means to maintain the structural stability of a hybrid organic–inorganic perovskite for efficient and robust photovoltaic applications. Here we present a theoretical, first-principles study of the electronic and energetic properties of the solid solution (CH(NH2)2)x(CH3NH3)1–xPbBryI1–y, the mixing of two organic molecules with various orientations, formamidinium and methylammonium, and two halides, bromide and iodide. Our results show the variation in the band gap as a function of composition (x and y) provides several candidates that exceed the 27.5% Schockley–Queisser efficiency. The variation in the composition of hybrid perovskite shows specific regions where either the hexagonal or cubic phase dominates. We discuss the balance between the band gap and phase stability and indicate regions where the phase transition temperature between cubic and hexagonal phases is far from room temperature, indicating that these compositions are more robust at room temperature against phase transitions

    Transport behavior of holes in boron delta-doped diamond structures

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    Boron delta-doped diamond structures have been synthesized using microwave plasma chemical vapor deposition and fabricated into FET and gated Hall bar devices for assessment of the electrical characteristics. A detailed study of variable temperature Hall, conductivity, and field-effect mobility measurements was completed. This was supported by Schr€dinger-Poisson and relaxation time o calculations based upon application of Fermi’s golden rule. A two carrier-type model was developed with an activation energy of 0.2eVbetweenthedeltalayerlowestsubbandwithmobility0.2 eV between the delta layer lowest subband with mobility 1 cm2/Vs and the bulk valence band with high mobility. This new understanding of the transport of holes in such boron delta-doped structures has shown that although Hall mobility as high as 900 cm2/Vs was measured at room temperature, this dramatically overstates the actual useful performance of the device

    Audio versus written feedback: exploring learners’ preference and the impact of feedback format on students’ academic performance

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    Very little is known about the impact of the different types of feedback on students’ academic performance. This paper explores students’ preference in the use of audio and written feedback and how each type of feedback received by students impact on their academic performance in subsequent assignments. The study involved 68 students who were divided into two groups that received either audio or written feedback in their first assignment which was then recalled and applied into the second assignment. An analysis of results obtained in the second assignment was conducted and comparisons made between students in the audio and written feedback group. Students were also surveyed using an online questionnaire to ascertain their perceptions about the type of feedback they had received. The study established that the type of feedback received did not impact on students’ grades in the subsequent assignment. In addition, while students were broadly positive about audio feedback, they indicated a strong preference for written feedback in future assignments. The study recommends, among other things, further investigation into the link between students’ learning styles and their preferences for different types of feedback

    The lattice dynamics and thermal properties of nanostructures

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    Strategies for coping with unexpected uptake of CBA

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    Sheffield Hallam University (SHU) has used the virtual learning environment (VLE), Blackboard since February 2001. The academic year of 2002-03 has seen an unexpected growth in the use of online assessments. The University's Learning, Teaching and Assessment strategy seeks to actively encourage the appropriate use of C&IT in teaching and learning in order to provide flexible learning opportunities for a diverse student population. Whilst SHU's assessment guidance permits the use of computer-based examinations, there are no explicit procedures and code of practice for staff to follow should they wish to introduce Computer Based Assessment (CBA) into their course design. This paper will explore the issues that arise when unexpectedly large numbers of staff avail themselves of an easy to use virtual learning environment with a built-in assessment system. There are both tensions and opportunities in this situation and we will describe successes as well as things which could have gone better

    Effect of metal intermixing on the Schottky barriers of Mo(100)/GaAs(100) interfaces

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    he electronic and structural properties of Mo(100)/GaAs(100) interfaces and Mo diffusion into GaAs are explored using first principle calculations. Our results show that the interface undergoes substantial atomic rearrangement with respect to the bulk structures and the bilayer of the GaAs adjacent to the interface becomes conducting. We study the n-type Schottky barrier height's dependence on Mo interdiffusion in the GaAs, with values ranging from ∌0.9 eV to ∌1.39 eV. This range is caused by the diffusants acting as additional n–type doping at the surface and their interaction with the metal-induced gap states
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