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    The growth of the chick femur in ova and its growth and repair in vitro and on the chorioallantoic membrane

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    The in ova growth of the femur of the chick Gallus gallus was investigated between 9 and 19 days of incubation. The growth and repair of the 14 day embryonic femur was studied in vitro and when cultured on the chorioallantoic membrane (CAM) of a host chick.In ova, 9 day femurs underwent a 100 fold increase in wet weight, dry weight, collagen and calcium. The relationship of femur growth to embryo wet weight changed during development and consequently embryo wet weight was an unreliable indicator of femur growth. Similarly femur wet weight and all parameters in matched tibias were poor indicators of femur mineralisation. There was a poor but acceptable correlation between femur dry weight and femur mineralisation.Hepes buffered medium was shown to be unsuitable for the culture of embryonic femurs. In bicarbonate buffered medium growth and osteogen-esis occurred and some osteoid formed. In varying media composition and culture conditions mineralisation and fracture repair were absent. Growth and osteogenesis but not mineralisation or repair were improved by adding 10% foetal calf serum but was still insignificant compared with in vivo growth.14 day old embryonic femurs, cultured on the CAM for 10 days, underwent a 10 fold increase in wet weight, dry weight, collagen content and mineralisation. After two days of culture their growth rate and morphology were similar to in vivo growth. Contralateral femurs cultured in separate eggs grew at a similar rate indicating a persistence of intrinsic control factors. The size of skeletal tissue that can be cultured on the CAM is significantly greater than was previously accepted. Fracture repair of damaged femurs occurred with mineralised tissue formed in the fracture gap. The model is suitable for the study of skeletal cell interactions, osteoclastic invasion, the toxicity of implant materials and the quantification of skeletal tissue growth and repair.</p

    Influence of anisotropic thermal conductivity in the apparatus insulation for sublimation growth of SiC: Numerical investigation of heat transfer

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    Geiser, Jürgen; Klein, Olaf; Philip, Peter. (2005). Influence of anisotropic thermal conductivity in the apparatus insulation for sublimation growth of SiC: Numerical investigation of heat transfer. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/4142

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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