1,720,957 research outputs found
Long Term Effects of Early Embryonic Ethanol Exposure, on Behavioural Performance and Learning in Zebrafish, Danio rerio
Get PDFBackground: Fetal alcohol syndrome (FAS) is a devastating disorder whose mechanisms may be best investigated using animal models. Here we present a novel zebrafish FAS model to investigate the effects of low to moderate alcohol exposure during early development on learning.
Methods: At 24-hours postfertilization zebrafish embryos were exposed to low doses of ethanol (external concentrations = 0.00, 0.25, 0.50, 0.75 and 1.00% vol/vol) for a very short duration (2 hours). Upon adulthood associative learning in the zebrafish was tested in a plus maze.
Results: This exposure led to no gross anatomical abnormalities or increased morbidity or mortality. Overall activity was not significantly affected by embryonic ethanol exposure. A trend towards a dose-dependent decrease in learning and memory performance was observed. Conclusions: We suggest that zebrafish will be an appropriate model with which one can analyze the behavioural effects of embryonic alcohol exposure and the mechanisms of the ensuing abnormalities.MAS
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Long Term Effects of Early Embryonic Ethanol Exposure, on Behavioural Performance and Learning in Zebrafish, Danio rerio
No full textBackground: Fetal alcohol syndrome (FAS) is a devastating disorder whose mechanisms may be best investigated using animal models. Here we present a novel zebrafish FAS model to investigate the effects of low to moderate alcohol exposure during early development on learning.
Methods: At 24-hours postfertilization zebrafish embryos were exposed to low doses of ethanol (external concentrations = 0.00, 0.25, 0.50, 0.75 and 1.00% vol/vol) for a very short duration (2 hours). Upon adulthood associative learning in the zebrafish was tested in a plus maze.
Results: This exposure led to no gross anatomical abnormalities or increased morbidity or mortality. Overall activity was not significantly affected by embryonic ethanol exposure. A trend towards a dose-dependent decrease in learning and memory performance was observed. Conclusions: We suggest that zebrafish will be an appropriate model with which one can analyze the behavioural effects of embryonic alcohol exposure and the mechanisms of the ensuing abnormalities.MAS
Variations on the Author
Get PDF“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
Get PDFWe 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
Fishing for a Zebrafish model of Fetal Alcohol Spectrum Disorder: The Behavioural Characterization and a Biological Exploration of the Effects of Embryonic Alcohol Exposure on Zebrafish
No full textFetal alcohol spectrum disorder (FASD) is the leading cause of birth defects in the Western world. Individuals with FASD may suffer from physical deformities and /or behavioural and cognitive impairments that are life long, severely reducing their quality of life while placing a financial burden on society. In order to address the aforementioned issues it is necessary to unravel the mechanisms underlying FASD. Animal models can aid in elucidating the mechanisms involved in FASD. The zebrafish possess a number of behavioural and biological characteristics making them a suitable animal model for FASD research. In the past this species has been used to explore the effects of embryonic alcohol exposure (EAE) on physical features. While a few studies have begun to investigate the impact EAE has on social behaviour, these studies utilized a live group of zebrafish (shoal) to assay the behaviour. Previously, I demonstrated that a computerized shoal could be used to study the behavioural deficits associated with EAE; specifically, I found a dose-dependent decrease in social behaviour in exposed fish. The research presented within this thesis represents an expansion of my previous research. Beginning by optimizing the parameters of the computerized stimulus, I was able to demonstrate that the size and the number of fish within the animated shoal effects the social behaviour of experimental fish. Using the optimized social paradigm, I showed that the deficits in social behaviour caused by EAE are stage-specific and that these social impairments do not subside with age. I used high-pressure liquid chromatography to determine whether the changes in social behaviour caused by EAE were accompanied by changes to the dopamine system, finding that EAE did impair the dopaminergic system. I was also successful at developing a new apparatus that is capable of assaying many behaviours in zebrafish, including associative learning and memory.Ph.D
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
- …
