1,720,995 research outputs found

    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

    Molecular identification of Sarcocystis spp. in foxes (Vulpes vulpes) and raccoon dogs (Nyctereutes procyonoides) from Germany

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    More than 200 Sarcocystis spp. have been named and most of them appear to be involved in a particular predator-prey cycle. Among canids, the European fox (Vulpes vulpes) and the raccoon dog (Nyctereutes procyonoides) are widely distributed in Europe and probably play an important role as definitive hosts in the epidemiology of Sarcocystis spp. infections. A total of 50 small intestines from foxes and 38 from raccoon dogs were sampled in the Federal State of Brandenburg, Germany. Mucosal scrapings were collected and analyzed by sugar flotation and when oocysts or sporocysts were detected, an overnight sedimentation was performed and DNA extracted with a commercial kit. A PCR was conducted using primers targeting a fragment of the 18S rRNA gene (with a size of approximately 850 bp) and the amplicons were purified and sequenced. Samples with an inconclusive sequencing were cloned into plasmids and ≥ 3 plasmids from each amplicon were sequenced. Sarcocystis spp. oocysts/sporocysts were detected in 38% (19/50) of fox and 52.6% (20/38) of raccoon dog samples. Sequencing analysis of amplicons from oocyst DNA revealed mixed infections in 9 fox and 5 raccoon dog samples. In the fox samples, the most often identified Sarcocystis spp. were S. tenella or S. capracanis (10.0%); S. miescheriana (8.0%) and S. gracilis (8.0%) followed by Sarcocystis spp., which use birds as intermediate hosts (6.0%), and S. capreolicanis (4.0%). In the raccoon dog samples, sequences with a ≥99% identity with the following species were detected: S. miescheriana (18.4%), S. gracilis (13.1%), Sarcocystis spp. using birds as IH (10.5%), S. tenella or S.capracanis (2.6%) and S. capreolicanis (2.6%). The estimated prevalence of Sarcocystis spp. infections determined using mucosal scrapings was higher than in related studies performed by analyzing faecal samples. The methodology of 18S rRNA gene amplification, cloning and sequencing is suitable to identify mixed infections with Sarcocystis spp. and to gather information on potential definitive hosts of these parasite species.Fil: Moré, Gastón Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; Argentina. Friedrich-Loeffler-Institut. Federal Research Institute for Animal Health. Institute of Epidemiology; AlemaniaFil: Maksimov, A.. Friedrich-Loeffler-Institut. Federal Research Institute for Animal Health. Institute of Epidemiology; AlemaniaFil: Conraths, F. J.. Friedrich-Loeffler-Institut. Federal Research Institute for Animal Health. Institute of Epidemiology; AlemaniaFil: Schares, G.. Friedrich-Loeffler-Institut. Federal Research Institute for Animal Health. Institute of Epidemiology; Alemani

    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

    Dogs shed Neospora caninum oocysts after ingestion of naturally infected bovine placenta but not after ingestion of colostrum spiked with Neospora caninum tachyzoites

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    An experiment was carried out to determine whether bovine colostrum or placenta could be a source of infection of Neospora caninum for dogs. For this purpose, two dogs were fed bovine colostrum to which culture-derived N. caninum tachyzoites were added and two other dogs were fed placental cotyledonary tissue from N. caninum seropositive cows. One dog served as a negative control during the start of the experiment but this control dog was fed cotyledonary tissue later on. None of the dogs did produce serum antibodies to N. caninum. All three dogs that were fed cotyledonary tissue did shed N. caninum oocysts, but no oocyst shedding was seen in the two dogs that were fed colostrum with N. caninum tachyzoites. Oocyst excretion did not resume in two dogs after repeated feeding of N. caninum infected placenta. The identity of the oocysts was confirmed by a bioassay in gerbils. It is concluded that ingestion of bovine placenta by dogs is an effective mode of transmission of N. caninum from cattle to dogs.LR: 20061115; PUBM: Print; JID: 0314024; 0 (Antibodies, Protozoan); ppublishSource type: Electronic(1

    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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