1,721,042 research outputs found
Evolutionary dynamics of RNA viruses with zoonotic potential
Full text linkRNA viruses with zoonotic potential represent a public health threat throughout the world. High mutation rates, short generation times and large population sizes are three factors responsible for their high genetic variability and enormous adaptive capacity to new environmental conditions. Understanding the genetic properties and the evolutionary dynamics of RNA viruses with zoonotic potential is crucial to prevent, control, treat and lessen the damage to animal and human health.
This thesis investigates the most essential aspects related to the evolution and epidemiology of two widespread zoonotic diseases caused by two RNA viruses: Avian Influenza and rabies. Through the application of bioinformatics tools, I analysed a large amount of sequence data, generated using both first and second generation sequencing technology, from viruses collected during four distinct epidemics: a fox-rabies virus epidemic occurred in north-eastern Italy between 2008 and 2011, highly pathogenic H5N1 avian influenza outbreaks reported in Egypt between 2006 and 2010, and two avian influenza epidemics caused by two distinct subtypes that took place in northern Italy from 1999 to 2001 and 2002 to 2004.
Through phylogenetic and Bayesian phylogeographic analyses of viral sequences sampled over multiple discrete spatio-temporal scales, the studies in this thesis reveal the co-circulation of multiple viral lineages, explore the viral gene flows and investigate the evolutionary dynamics of viruses under different selection pressures. In addition, to better understand the pattern of transmission of viral subpopulations from host to host, the intra-host variability and the evolution of viral pathogenicity, I employed an ultra-deep sequencing approach to assess the diversity of viral populations.
The data generated in this thesis provide important insights into the a) impact and efficacy of surveillance strategies and control measures implemented during an outbreak, b) differences in the evolutionary dynamics and spatial spread between distinct genetic groups, c) emergence of amino acid mutations that may increase viral fitness, d) inter-host transmission of viral variants and e) gain of virulence determinants.
Finally, this thesis shows the great opportunity offered by next generation sequencing technology for dramatic advancement in our understanding of the complicated evolutionary dynamics of these pathogen
Genetic diversity of H1, H2 and H3 subtypes of Influenza A circulating in wild birds in Italy, 2005–2010.
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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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