1,720,954 research outputs found
Hippocampal-dependent neuroimmune mechanisms are associated with the effect of ethanol on stress-enhanced fear learning
Get PDFThe neurobiological mechanisms underlying comorbid post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) are not well understood. We have previously demonstrated that chronic ethanol consumption and withdrawal exacerbates future stress-enhanced fear learning, a rodent model of PTSD-like behavior, supporting the idea that prior ethanol dependence induces vulnerability to future stressors. We have also shown that dorsal hippocampal astrocytes play a functional role in the development of this behavior, implicating the neuroimmune system in this phenotype. Thus, the current dissertation first sought to investigate the impact of chronic ethanol consumption and withdrawal on interleukin-1β (IL-1β), a proinflammatory cytokine, and glial fibrillary acidic protein (GFAP), a marker for astrocytes in the dorsal hippocampus (DH). We found that IL-1β expression in the dentate gyrus (DG) of the DH was increased following severe stress, while chronic ethanol consumption and withdrawal increased the expression of GFAP. Importantly, astrocytes were found to be the primary cell-type source of IL-1β, and chronic ethanol consumption and withdrawal increased the colocalization of IL-1β with GFAP. Given this association between IL-1β and astrocytes, we tested the specific functional role of dorsal hippocampal astrocyte-derived IL-1β in ethanol-induced alterations in future PTSD-like behavior. We employed a novel CRISPR/Cas9 technique to knockdown Il1b gene expression in dorsal hippocampal astrocytes. After validating this new technique, we found that knockdown of Il1b in dorsal hippocampal astrocytes had a modest effect in reducing ethanol’s augmentation of stress-enhanced fear learning. Collectively, these data support a partial role of dorsal hippocampal IL-1β in mediating ethanol- and stress-enhanced fear learning. These data ultimately support the involvement of hippocampal neuroimmune mechanisms in the development of comorbid PTSD and AUD.Doctor of Philosoph
Chronic Ethanol Consumption Exacerbates Stress-Enhanced Fear Learning, an Effect Mediated by Dorsal Hippocampal Astrocytes
Get PDFAlcohol use disorder (AUD) and post-traumatic stress disorder (PTSD) are highly comorbid, yet there is a lack of research investigating how prior ethanol dependence influences the development of PTSD-like behavior. Thus, an ethanol liquid diet model was combined with the stress-enhanced fear learning (SEFL) paradigm to investigate the effects of chronic ethanol consumption on the development of a PTSD-like phenotype. Interestingly, chronic ethanol consumption and withdrawal exacerbates future SEFL, and significantly increases glial fibrillary acidic protein (GFAP) mRNA expression in several brain regions, including the dorsal hippocampus (DH). Therefore, the functional contribution of DH astrocytes in the development of SEFL in ethanol-dependent rats was tested by stimulating astrocyte-specific Gi designer receptors exclusively activated by designer drugs (Gi-DREADDs) during withdrawal, which prevented ethanol-induced enhancement of SEFL. Overall, these studies provide crucial insight into the potential neurobiological mechanisms behind increased susceptibility to a PTSD-like phenotype in individuals with AUD.Master of Art
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
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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