1,721,180 research outputs found
Using zebrafish to assess developmental neurotoxicity
It is widely accepted that the developing nervous system is especially vulnerable to a variety of chemicals, including drugs and environmental contaminants. It is also clear that our understanding of the risks from chemical exposures during development is rudimentary, and that the resources for remedying the situation are legion. As a result, increasing attention is directed toward alternative test methods including in vitro preparations, computational (in silico) models, and in vivo model (or alternative) organisms. In particular, zebrafish have become a popular test species in toxicology, pharmacology, and biomedical research. In this chapter, we review several issues, results, and research needs regarding the use of zebrafish to assess developmental neurotoxicity. Considerable advances have been made in understanding the basic biology of nervous system development in zebrafish, in techniques for rapidly evaluating the effect of chemical exposures on nervous system development, and, notably, to a lesser extent, in understanding the significance of results for predicting human effects. This chapter was written as an introduction to the use of zebrafish in developmental neurotoxicology, and to encourage the use of this model either for screening or mechanistic purposes. We have endeavored to make the reader aware of significant research findings, and to offer a balanced view of the advantages and limitations in using zebrafish as a model for investigating developmental neurotoxicity
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Using zebrafish to assess developmental neurotoxicity
It is widely accepted that the developing nervous system is especially vulnerable to a variety of chemicals, including drugs and environmental contaminants; however our understanding of the risks from chemical exposures during development is rudimentary. Zebrafish have become a popular test species in toxicology, pharmacology, and biomedical research. This chapter was written as an introduction to the use of zebrafish in developmental neurotoxicology, and to encourage the use of this model either for human or ecological risk characterizations. We have endeavored to make the reader aware of significant research findings, and to offer a balanced view of the advantages and limitations in using zebrafish as a model for investigating developmental neurotoxicity.</p
Dispelling the Myths Behind First-author Citation Counts
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
- …
