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    Morfo-Functional Adaptations of the Digestive System of the Cat Induced by Domestication

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    This study was conducted to investigate the possible existence of microscopic morphological differences between the digestive tract of the domestic cat (F. catus) and the wildcat (F. s. silvestris), in order to observe whether and how domestication has had an impact on the domestic species. There is still a lot unknown about this feline (F. s. silvestris) and this study was helpful to gain knowledge about the intestinal histology of this species. In order to assess the microscopic structure of the intestine, samples were collected from 22 subjects of F. silvestris silvestris and 9 individuals of F. catus. Histological samples were observed to assess the size of the intestinal villi (height and width) and depth of the crypts. From the average value of each parameter, means were obtained for each species, and these were compared using the Student’s t-test. The results show that there is a significant difference in the size of the villi and intestinal crypts between the two species. As described in literature, the F. catus has a higher Intestinal Index (intestine length divided by body length) than the wildcat, which means the intestine in the domestic species is longer than in the wild species. Despite the domestication of the cat being a process not yet fully understood, based upon published studies, we can conclude that domestication, in particular the change in eating habits, had a major effect on the digestive system that should be studied and known in more detail

    Functional and morphological adaptations of the digestive system induced by domestication in cats.

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    Several studies have showed the macroscopic difference in the gastrointestinal tract between the European wildcat (Felis silvestris silvestris) and the domestic cat (Felis silvestris catus). Digestive system in the wildcat is shorter than in domestic species and this feature is considered distinctive in the taxonomic classification of subjects (Schauenberg et al. 1977). This study is a part of a large investigation regarding the microscopic anatomy of the gastrointestinal tract of European wildcat, associated to the study of intestinal microbiome. Its main purpose was to enhance knowledge about this species, to get a comparison with domestic cat, and to evaluate if and how domestication has influenced the functional and morphological development of this apparatus, also n n t ut‘s m roflor To this aim we collected, weighted and measured the gastrointestinal tract of twenty European wildcats. Afterwards, intestinal sections were sampled, treated and observed at the microscope in order to evaluate histological characteristics as the villi height and width, crypts depth and wall thickness. Moreover, we wanted to study the intestinal production of an apolipoprotein that is believed directly related to the development of hepatic steatosis, decreasing the amount of lipids deposited in the liver. For this purpose, liver specimens were collected and treated to study histologically the degree of vacuolar degeneration of hepatocytes. Data were analyzed and compared with those of the domestic cats coming from our database. In attempt to evaluate the microbiome, feces and rectal ampulla were collected and sent to the Texas A&M University for pyrosequencing analysis (data not shown). Results demonstrated significant differences in intestinal structure between F. catus and F. s. silvestris. Villi coming from domestic cats were significantly shorter (p<0.0001) and wider (p<0.0142) than in wildcats that showed crypts deeper (p<0.0009). Domestication has led to significant changes in adaptation regarding both behavior and diet. Several studies showed the correlation between diet changes (protein, carbohydrates, and fiber concentration) and morphological adaptation in the gut of different species (Altmann, 1972; Hampson, 1983; Goodlad et al., 1988; Pluske et al., 1996; Sritiawthai et al., 2013). Moreover, data from liver study showed that domestic cat has higher levels of apolipoprotein compared to the wild cat and that the percentage of lipids in the liver was lower in F. catus than in F. s. silvestris. Despite these results, the liver of domestic cat revealed a rate of steatosis higher than in wild cat. Indeed, this pathology proved to be almost absent in wild cats and can be explained by the different nature of the two species diet and microbiome composition. This study revealed that transition from a strictly-carnivorous diet (typical of the wild cat) to an omnivorous type, has modified the nutritional intake considerably and influenced the evolution of the digestive apparatus in domestic cat

    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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