1,720,960 research outputs found
Olfactory Communication in Rats: A Mechanism for Information Centre Functioning
Full text linkThe present research investigates whether information concerning distant foods can be exchanged by domestic rats at a central site. Experiments were designed to model a natural situation in which a successful forager ("demonstrator" rat) returns to the burrow (home cage) and interacts briefly with a fellow colony member ("observer" rat).Information transfer was demonstrated, as observers exhibited a marked preference for the food that their demonstrators had eaten. A series of experiments designed to analyze the means of information exchange demonstrated that communication was mediated by olfactory cues. Active communication regarding the demonstrator's feeding success proved unnecessary for effective information transfer between demonstrators and observers. Finally, observers exposed to poisoned demonstrators during the interaction period, nevertheless exhibited a preference for the food that their demonstrators had eaten. This result suggested that observers had failed to associate olfactory cues regarding the food with their demonstrators' illness.Master of Arts (MA
The role of residual olfactory cues in the determination of the feeding site selection and exploration patterns of domestic rats
No full textThe results of the present series of experiments indicate that weanling domestic rat pups feed and explore in areas containing residual olfactory cues deposited by conspecific adults in preference to clean areas. Both nulliparous and lactating Long-Evans female rats can mark an area so as to induce pups to explore and feed in it. Residual cues continue to affect the feeding and exploratory behavior of pups to maturity. Discrepancies between the results obtained in the olfactory discrimination apparatus (Leon &Moltz, 1971) and the present experiments are resolved and evidence presented for the existence of residual cues attractive to pups not contained in anal excreta. It is. suggested that residual cues deposited by adult rats can playa role in directing weanlings to their first meals of solid food in the natural environment.Master of Arts (MA
Análisis de los procesos de aprendizaje social que afectan elecciones alimenticias y sexuales en animales
No full textSocial influences on the mate choices of male and female Japanese quail
No full textFor the last decade, Japanese quail (Coturnix japonica) have served as subjects in an extended series of studies of social influences on reproductive behavior. The results of those studies are summarized here. Females prefer to affiliate with males that they have seen courting and mating, whereas males avoid females that they have seen courting and mating, and both males and females prefer to copulate with the same individuals with whom they prefer to affiliate. Further, females lay more fertilized eggs after mating with a male they have seen mate with another female than after mating with a male they did not watch while he mated. Female quail’s preferences among males are also affected by observation of males ’ aggressive interactions, with virgin females preferring dominant males and sexually experienced females preferring subordinates. Evidence is provided suggesting that: (1) responses of quail to observation of a member of the opposite sex mating is an adaptive specialization of information processing systems involved in quail social learning and (2) mate-choice copying in quail can influence the evolution of male secondary sexual characteristics
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
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