1,720,954 research outputs found
Modulation of anxiety by the endocannabinoid anandamide signaling in the prefrontal cortex is dependent on the emotional arousal state
No full textMany people who suffer from anxiety disorders self-medicate with cannabis which seems to reduce anxiety. However, cannabis usage has also been shown to have the opposite effect and some people have reported feeling increased anxiety and depressive mood when using cannabis. Animal studies have indicated that cannabinoid drugs can cause these distinct opposite effects on anxiety behaviour depending on both the animal stress levels and the aversiveness of the environmental conditions. Furthermore, animal studies have shown the critical involvement of the prefrontal cortex (PFC) endocannabinoid system in the regulation of stress and anxiety behaviours. The goal of this study was to evaluate whether the endocannabinoid anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in the PFC, differentially regulate anxiety behaviour depending on the level of environment-associated emotional arousal.
Sprague-Dawley rats were divided in two groups and tested for anxiety in the Elevated Plus Maze (EPM). To increase the level of environment-associated emotional arousal, one group was not handled or habituated to the experimental room and tested under high light condition (High-Arousal group; HA); the second group was extensively handled and habituated to the experimental room prior to the EPM and tested under red light condition (Low-Arousal group; LA). We evaluated the effects of intra-PFC administration of the AEA hydrolysis inhibitor URB597 or the 2-AG hydrolysis inhibitor KML29 on anxiety behavior. HA and LA rats were given bilateral intra-PFC administration of URB597 (10 ng/side), KML29 (0.2ug/side) or their vehicle 30 min prior to the EPM test. Rats were, then, sacrificed for brain dissection and histological analysis to assure proper cannula placement. As was expected, the LA group exhibited a significant lower anxiety behavioral profile as compared to the HA group in the EPM. We also found that URB597 decreased the anxiety response shown by LA rats as compared to the correspondent vehicle group, without affecting emotional behavior in the HA group. KML29 injections did not alter anxiety response in the LA or the HA group.
Taken together, these findings show how the endocannabinoid system is differentially activated to regulate anxiety response, depending on the level of the environment-associated emotional arousal and help to shed light on the neurobiological mechanism involved in the differential impact of stress on emotionality
Modulation of anxiety by the endocannabinoid anandamide signaling in the prefrontal cortex is dependent on the emotional arousal state
No full textCannabinoids can cause distinct and opposite effects on anxiety behaviour depending on the stress level and the aversiveness of the environmental conditions.
Aim: We evaluated whether the endocannabinoid anandamide and 2-arachidonoylglycerol, in the prefrontal cortex (PFC), differentially regulate anxiety depending on the level of environment-associated emotional arousal.
Methods: Rats were divided in two groups and tested for anxiety in the Elevated Plus Maze (EPM). To increase the level of environment-associated emotional arousal, one group was not handled or habituated to the experimental room and tested under high light condition (High-Arousal group; HA); the second group was handled and habituated to the experimental room and tested under red light condition (Low-Arousal group; LA). We measured anandamide and 2-arachidonoylglycerol levels immediately after the EPM, in the PFC, and tested the effects of intra-PFC administration of the anandamide hydrolysis inhibitor URB597 and the 2-arachidonoylglycerol hydrolysis inhibitor KML29 on anxiety, in HA and LA rats.
Results: As expected, the HA group exhibited significant higher anxiety as compared to the LA group. In addition, HA rats showed decreased anandamide levels in the PFC as compared to their home cage control group. Moreover, URB597 increased the anxiety response shown by LA rats without affecting emotional behavior in the HA group. KML29 injections did not alter anxiety response in the LA or the HA group.
Conclusions: These findings show that the endocannabinoid system in the PFC is differentially activated to regulate anxiety, depending on the level of the environment-associated emotional arousal
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
