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    Intervertebral disc degeneration in dogs

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    Back pain is common in both dogs and humans, and is often associated with intervertebral disc (IVD) degeneration. The IVDs are essential structures of the spine and degeneration can ultimately result in diseases such as IVD herniation or spinal instability. In order to design new treatments halting or even preventing IVD degeneration, more basic knowledge of the disease process is needed. The aim of this thesis was to increase the knowledge of IVD degeneration in dogs and to evaluate the similarities and differences between IVD degeneration in dogs and humans, in order to establish whether spontaneous IVD degeneration occurring in both chondrodystrophic (CD) and non-chondrodystrophic (NCD) dog breeds can be used as translational animal models for human spine research. The key findings of the thesis were: • The division of the processes underlying canine IVD degeneration into chondroid or fibroid degeneration appears to be inaccurate. The biochemical, histopathological, and morphological alterations examined during the process of IVD degeneration were found to be similar in CD and NCD dog breeds. • IVD degenerative diseases were most common in CD breeds, especially in Dachshunds, and were 1.5 times more common in male than female dogs. Case fatality rates were found to be higher than previously suggested, with rates of 34% in the overall population, around 20% in most CD breeds, and over 50% in the NCD breeds at highest risk such as the Doberman and the German Shepherd Dog. • IVD degeneration in dogs could accurately be diagnosed, early in the degenerative process, by using low-field magnetic resonance imaging (MRI). The MRI based grading scheme used in humans could reliably be used in dogs, and was found to be highly correlated with pathological changes found post mortem. Early diagnosis facilitates the possibility of preemptive treatments. • A new nucleus pulposus prosthesis, made of an intrinsically radiopaque hydrogel, was tested ex-vivo in dogs. Surgical implantation of the prosthesis in canine lumbosacral IVDs via a dorsal laminectomy was clinically applicable. After absorbing fluid from the surrounding tissue the swollen implant could restore disc height, which could be monitored by radiography, computed tomography and MRI. • Many similarities were found between the processes of IVD degeneration in humans and CD and NCD dog breeds. Both dog-types may serve as translational animal models of spontaneous IVD degeneration for human research. Synergistic effects of studying IVD degeneration in veterinary patients could lead to new treatment modalities for both dogs and humans, a reduced need for animal testing, and lower cost of research. It is also likely that spontaneous IVD degeneration in dogs more resembles the true disease process, as it occurs in humans, than induced IVD degeneration in experimental animals

    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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