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An established preference for a conditioned stimulus associated with either sucrose or copulation in male rats subsequently shifts to a preference for a conditioned stimulus paired with cocaine self-administration
No full textIt is often assumed that a characteristic of drug addiction is a loss of interest in natural rewards concomitant with a heightened interest in drug rewards. To test this idea, we gave male rats a choice between a conditioned stimulus associated with a natural reward (sex or sucrose) and a conditioned stimulus associated with cocaine. In the first experiment, male rats were given five trials in which an odor (either lemon or almond) was associated with copulation to ejaculation with a sexually receptive female. Males were then given a choice between the odor-sex testing box and a neutral box (Day 1:15- min test). Rats showing a clear preference for the odor (n=10) then learned to self-administer cocaine in the presence of the other odor. After 3 cocaine sessions given on 3 consecutive days, they were given a choice test between the odor-sex and the odor-cocaine boxes (Day 10). The following day, there was an additional odor-sex pairing after which there were three additional days of odor-cocaine self-administration. Odor choice tests were given subsequently on Days 17, 24 and 38 without additional training. The odor preference of all rats did not shift immediately,but by day 38, 70% of the males chose the cocaine-paired odor. In Experiment 2, parallel results were observed in males (n=12) first trained to associate an odor with lever-pressing for sucrose pellets and then tested for the odor-sucrose box preference on Day 1. After training to self- administer cocaine in the presence of the second odor, rats developed a quick and consistent preference for the odor associated with cocaine. These results provide preliminary evidence that cocaine induces a preference shift in rats away from stimuli associated with natural rewards to stimuli paired with repeated drug self- administration. These experiments also demonstrate the effectiveness of the method for the further study of the phenomenon
An established preference for a conditioned stimulus associated with either sucrose or copulation in male rats subsequently shifts to a preference for a conditioned stimulus paired with cocaine self-administration.
No full textAn established preference for a conditioned stimulus associated with either sucrose or copulation in male rats subsequently shifts to a preference for a conditioned stimulus paired with cocaine self-administration
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
Questionnaires for assessment of female sexual dysfunction: a review and proposal for a standardized screener.
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