1,011 research outputs found

    Variable Appropriation of an Online Resource Discovery and Sharing Tool

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    Even when following best practices for participatory design, the appropriation of tools in formal education settings can be hampered by a number of factors. Drawing from a case of a web tool built to help teachers in five school districts find and share free resources in an educational digital library, we describe patterns of tool use and provide some explanations for variability in tool appropriation. We also suggest that future research consider school districts as complex systems of professionals whose interactions and inter-relationships may yield unexpected technology adoption behaviors

    What a Long Strange Trip Itā€™s Been: A Comparison of Authors, Abstracts, and References in the 1991 and 2010 ICLS Proceedings

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    We examine differences in authorship, word usage, and references in full papers from the 1991 and 2010 ICLS proceedings. Through a series of analyses, we observe that, while authors largely hail from the US, national and regional participation in the LS community has broadened. Word usage suggests a shift in emphasis from cognitive issues to ones that are both cognitive and cultural. Reference analysis indicates a shift in core literatures and influential authors

    Intralocus sexual conflict can resolve the male-female health-survival paradox

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    This is the final version. Available on open access from Springer Nature via the DOI in this recordAt any given age, men are more likely to die than women, but women have poorer health at older ages. This is referred to as the ā€œmale-female, health-survival paradoxā€, which is not fully understood. Here, we provide a general solution to the paradox that relies on intralocus sexual conflict, where alleles segregating in the population have late-acting positive effects on male fitness, but negative effects on female health. Using an evolutionary modelling framework we show that male-benefit, female-detriment alleles can spread if they are expressed after female reproduction stops. We provide support for our conflict based solution using experimental Drosophila data. Our results show that selecting for increased late-life male reproductive effort can increase male fitness but have a detrimental effect on female fitness. Furthermore, we show that late-life male fertility is negatively genetically correlated with female health. Our study suggests that intralocus sexual conflict could resolve the health-survival paradoxWe thank the National Science Center (Poland: 2013/09/N/NZ/NZ8/03231) and the Leverhulme Trust (UK: RF-2015-01) for funding which partially supported this work, and the University of Exeterā€™s Deanā€™s Fellowship for additional support

    Conjecture Mapping the Library: Iterative Refinements Toward Supporting Maker Learning Activities in Small Community Spaces

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    A recent and important innovation in design-based research (DBR) is the use of conjecture maps, where researchers explicitly articulate the conjectured mediational relations between their designed goals and the learning designs and contexts. In this paper, we present a design case as an iterative sequence of evolving conjecture maps. As each conjecture map was tested, we revised it to highlight and refine our articulation of the tools and processes that embodied our design approach. Out design case involves small-town and rural community and school libraries in the United States as partners and DBR sites, with the goal of supporting librarians as they learn to develop and enact new STEM-oriented maker programs for youth. We show how conjecture mapping informed and supported our DBR work and how it helped push for specificity in hypothesized relations between the design, the learning setting, the outcomes. while also forcing a refection on design constraints

    QTL Fine Mapping by Measuring and Testing for Hardy-Weinberg and Linkage Disequilibrium at a Series of Linked Marker Loci in Extreme Samples of Populations

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    It has recently been demonstrated that fine-scale mapping of a susceptibility locus for a complex disease can be accomplished on the basis of deviations from Hardy-Weinberg (HW) equilibrium at closely linked marker loci among affected individuals. We extend this theory to fine-scale localization of a quantitative-trait locus (QTL) from extreme individuals in populations, by means of HW and linkage-disequilibrium (LD) analyses. QTL mapping and/or linkage analyses can establish a large genomic region (āˆ¼30 cM) that contains a QTL. The QTL can be fine mapped by examination of the degree of deviation from HW and LD at a series of closely linked marker loci. The tests can be performed for samples of individuals belonging to either high or low percentiles of the phenotype distribution or for combined samples of these extreme individuals. The statistical properties (the power and the size) of the tests of this fine-mapping approach are investigated and are compared extensively, under various genetic models and parameters for the QTL and marker loci. On the basis of the results, a two-stage procedure that uses extreme samples and different tests (for HW and LD) is suggested for QTL fine mapping. This two-step procedure is economic and powerful and can accurately narrow a genomic region containing a QTL from āˆ¼30ā€“1 cM, a range that renders physical mapping feasible for identification of the QTL. In addition, the relationship between parameterizations of complex diseases, by means of penetrance, and those of complex quantitative traits, by means of genotypic values, is outlined. This means that many statistical genetic methods developed for searching for susceptibility loci of complex diseases can be directly adopted and/or extended to QTL mapping for quantitative traits

    Recent Advances in Proteomics and Cancer Biomarker Discovery

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    Early diagnosis and prevention is a key factor in reducing the mortality and morbidity of cancer. However, currently available screening tools lack enough sensitivity for early diagnosis. It is important to develop noninvasive techniques and methods that can screen and identify asymptomatic patients who have cancer. Biomarkers of cancer status can also serve as powerful tools in monitoring the course of cancer and in determining the efficacy and safety of novel therapies. Thus, discovery of novel specific biomarkers are needed that may provide informative clues for early diagnosis and treatment of cancer. Recently, remarkable progress has been made in the development of new proteomics technology. The progress that has been made in this field is helpful in identifying biomarkers that can be used for early diagnosis of cancer and improving the understanding of the molecular etiological mechanism of cancer. This article describes the current state of the art in this field

    Design for Co-Design in a Computer Science Curriculum Research-Practice Partnership

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    This paper reports on a study of the dynamics of a Research-Practice Partnership (RPP) oriented around design, specifically the co-design model. The RPP is focused on supporting elementary school computer science (CS) instruction by involving paraprofessional educators and teachers in curricular co-design. A problem of practice addressed is that few elementary educators have backgrounds in teaching CS and have limited available instructional time and budget for CS. The co-design strategy entailed highlighting CS concepts in the mathematics curriculum during classroom instruction and designing computer lab lessons that explored related ideas through programming. Analyses focused on tensions within RPP interaction dynamics and how they were accommodated when RPP partners were designing for co-design activities, a critical component that leads to curricular co-design itself. We illustrate these tensions with examples of clusters of activity that appeared repeatedly among the research and practice team members when designing for co-design

    Harold M. Frost T J Musculoskel Neuron Interact 2001; 2(2):117-119 William F. Neuman Awardee 2001

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    Tribute to Harold M. Frost, honorary president of ISMNI, who received the William F. Neuman Award from the American Society of Bone and Mineral Research October 2001

    The effects of symmetry on the dynamics of antigenic variation

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    In the studies of dynamics of pathogens and their interactions with a host immune system, an important role is played by the structure of antigenic variants associated with a pathogen. Using the example of a model of antigenic variation in malaria, we show how many of the observed dynamical regimes can be explained in terms of the symmetry of interactions between different antigenic variants. The results of this analysis are quite generic, and have wider implications for understanding the dynamics of immune escape of other parasites, as well as for the dynamics of multi-strain diseases.Comment: 21 pages, 4 figures; J. Math. Biol. (2012), Online Firs

    Issues in modern bone histomorphometry

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    This review reports on proceedings of a bone histomorphometry session conducted at the Fortieth International IBMS Sun Valley Skeletal Tissue Biology Workshop held on August 1, 2010. The session was prompted by recent technical problems encountered in conducting histomorphometry on bone biopsies from humans and animals treated with anti-remodeling agents such as bisphosphonates and RANKL antibodies. These agents reduce remodeling substantially, and thus cause problems in calculating bone remodeling dynamics using in vivo fluorochrome labeling. The tissue specimens often contain few or no fluorochrome labels, and thus create statistical and other problems in analyzing variables such as mineral apposition rates, mineralizing surface and bone formation rates. The conference attendees discussed these problems and their resolutions, and the proceedings reported here summarize their discussions and recommendations
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