1,659 research outputs found

    Epitaxial checkerboard arrangement of nanorods in ZnMnGaO4 films studied by x-ray diffraction

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    The intriguing nano-structural properties of a ZnMnGaO4 film epitaxially grown on MgO (001) substrate have been investigated using synchrotron radiation-based x-ray diffraction. The ZnMnGaO4 film consisted of a self-assembled checkerboard (CB) structure with perfectly aligned and regularly spaced vertical nanorods. The lattice parameters of the orthorhombic and rotated tetragonal phases of the CB structure were analyzed using H-K, H-L, and K-L cross sections of the reciprocal space maps measured around various symmetric and asymmetric reflections of the spinel structure. We demonstrate that the symmetry of atomic displacements at the phases boundaries provides the means for coherent coexistence of two domains types within the volume of the film

    Physician network position and patient outcomes following implantable cardioverter defibrillator therapy

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150523/1/hesr13151.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150523/2/hesr13151_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150523/3/hesr13151-sup-0001-AuthorMatrix.pd

    Modeling peer effect modification by network strength: The diffusion of implantable cardioverter defibrillators in the US hospital network

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154422/1/sim8466.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154422/2/sim8466_am.pd

    Treasure codes: augmenting learning from physical museum exhibits through treasure hunting

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    Previous studies have highlighted the difficulty that designers face in creating mobile museum guides to enhance small group experiences. In this paper, we report a study exploring the potential of mobile visual recognition technology (Artcodes) to improve users’ experiences in a visitor centre. A prototype mobile guide in the form of a treasure hunt was developed and evaluated by means of a field study comparing this technology with the existing personal guided tour. The results reveal a preference for the mobile guide amongst participants and show significant learning gains from pre-test to post-test compared with the pre-existing personal tour. Our observational analyses indicate how the mobile guide can be used to improve visitors’ learning experiences by supporting active discovery and by balancing physical and digital interactions. We further expand the concept of design trajectories to consider micro-scaffolding as a way of understanding and designing future public technologies

    Cardiology providers’ recommendations for treatments and use of patient decision aids for multivessel coronary artery disease

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    Background: Rates of recommending percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) vary across clinicians. Whether clinicians agree on preferred treatment options for multivessel coronary artery disease patients has not been well studied. Methods and results: We distributed a survey to 104 clinicians from the Northern New England Cardiovascular Study Group through email and at a regional meeting with 88 (84.6%) responses. The survey described three clinical vignettes of multivessel coronary artery disease patients. For each patient vignette participants selected appropriate treatment options and whether they would use a patient decision aid. The likelihood of choosing PCI only or PCI/CABG over CABG only was modeled using a multinomial regression. Across all vignettes, participants selected CABG only as an appropriate treatment option 24.2% of the time, PCI only 25.4% of the time, and both CABG or PCI as appropriate treatment options 50.4% of the time. Surgeons were less likely to choose PCI over CABG (RR 0.14, 95% CI 0.03, 0.59) or both treatments over CABG only (RR 0.10, 95% CI 0.03, 0.34) relative to cardiologists. Overall, 65% of participants responded they would use a patient decision aid with each vignette. Conclusions: There is a lack of consensus on the appropriate treatment options across cardiologists and surgeons for patients with multivessel coronary artery disease. Treatment choice is influenced by both patient characteristics and clinician specialty

    Analytic regularity for a singularly perturbed system of reaction-diffusion equations with multiple scales: proofs

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    We consider a coupled system of two singularly perturbed reaction-diffusion equations, with two small parameters 0<ϔ≀Ό≀10< \epsilon \le \mu \le 1, each multiplying the highest derivative in the equations. The presence of these parameters causes the solution(s) to have \emph{boundary layers} which overlap and interact, based on the relative size of Ï”\epsilon and % \mu. We construct full asymptotic expansions together with error bounds that cover the complete range 0<ϔ≀Ό≀10 < \epsilon \leq \mu \leq 1. For the present case of analytic input data, we derive derivative growth estimates for the terms of the asymptotic expansion that are explicit in the perturbation parameters and the expansion order

    Adult beginner distance language learner perceptions and use of assignment feedback

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    This qualitative study examines perceptions and use of assignment feedback among adult beginner modern foreign language learners on higher education distance learning courses. A survey of responses to feedback on assignments by 43 Open University students on beginner language courses in Spanish, French, and German indicated that respondents can be classified into three groups: those who use feedback strategically by integrating it into the learning process and comparing it with, for example, informal feedback from interaction with native speakers, those who take note of feedback, but seem not to use it strategically, and those who appear to take little account of either marks or feedback. The first group proved to be the most confident and most likely to maintain their motivation in the longer term. The conclusion discusses some of the pedagogical and policy implications of the findings

    Who are these youths? Language in the service of policy

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    In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The ‘responsibilisation’ of young offenders and the ‘no excuses’ culture of youth justice have been ‘marketed’ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged

    Ecological Invasion, Roughened Fronts, and a Competitor's Extreme Advance: Integrating Stochastic Spatial-Growth Models

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    Both community ecology and conservation biology seek further understanding of factors governing the advance of an invasive species. We model biological invasion as an individual-based, stochastic process on a two-dimensional landscape. An ecologically superior invader and a resident species compete for space preemptively. Our general model includes the basic contact process and a variant of the Eden model as special cases. We employ the concept of a "roughened" front to quantify effects of discreteness and stochasticity on invasion; we emphasize the probability distribution of the front-runner's relative position. That is, we analyze the location of the most advanced invader as the extreme deviation about the front's mean position. We find that a class of models with different assumptions about neighborhood interactions exhibit universal characteristics. That is, key features of the invasion dynamics span a class of models, independently of locally detailed demographic rules. Our results integrate theories of invasive spatial growth and generate novel hypotheses linking habitat or landscape size (length of the invading front) to invasion velocity, and to the relative position of the most advanced invader.Comment: The original publication is available at www.springerlink.com/content/8528v8563r7u2742
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