1,720,965 research outputs found
Scent-Marking Behaviour in a Pack of Free-Ranging Domestic Dogs
No full textMost mammals scent-mark, and a variety of hypotheses have been put
forward to explain this behaviour. Most of our knowledge about scent
marking in domestic dogs comes from studies carried out on laboratory or
companion dogs, while few studies have been carried out on free-ranging
dogs. Here, we explored the functional significance of different scentmarking
behavioural patterns in a pack of free-ranging domestic dogs by
testing two non-exclusive hypotheses: the indirect territorial defence
and the dominance/threat hypotheses. Through direct observation, we
recorded the locations of dog scent marks (urination, defecation and
ground scratching) and information regarding the identity and posture of
the marking animal. We found evidence that markings are used by dogs
to form a ‘property line’ and to threaten rivals during agonistic conflicts.
Both males and females utilized scent marking to assert dominance and
probably to relocate food or maintain possession over it. Raised-leg urination
and ground scratching probably play a role in olfactory and visual
communication in both males and females. Urinations released by
females, especially through flexed-leg posture, may also convey information
about their reproductive state. Finally, our observations suggest that
defecation does not play an essential role in olfactory communication
among free-ranging dogs and that standing and squat postures are associated
with normal excretion. Our results suggest that many of the proposed
functions of marking behaviours are not mutually exclusive, and all
should be explored through detailed field and laboratory studies
Effect of affiliative and agonistic relationships on leadership behaviour in free-ranging dogs
No full textConsensus decisions about the nature and timing of group activities allow animals to maintain group
cohesiveness, but also entail costs because individuals often differ with respect to their optimal activity
budgets. Two mechanisms whereby animals reach a consensus include ‘consistent leadership’, in which
a single dominant individual makes the decision, and ‘variable leadership’ in which several group
members contribute to the decision outcome. Sharing of consensus decisions is expected to reduce
consensus costs to most group members. Both patterns are thought to emerge from the complexity of
social relationships of group members. We investigated the distribution of leadership during group
departures in two packs of free-ranging dogs, Canis lupus familiaris, and tested how its distribution
between individuals was affected by dominance rank-related affiliative and agonistic relationships.
Although leadership was not entirely concentrated on a single group member, both packs had a limited
number of habitual leaders. In the largest pack, the pattern of leadership changed from ‘variable’ to
nearly ‘consistent’ after its size had shrunk. Habitual leaders were usually old and high-ranking individuals.
However, high-ranking dogs that received affiliative submissions in greeting ceremonies were
more likely to lead than dominant dogs receiving submissions only in agonistic contexts. During resting
times, habitual followers associated more closely with habitual leaders than with other followers. These
results suggest that in social species collective movements may arise from the effort of subordinates to
maintain close proximity with specific valuable social partners
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
La qualità dell'immagine termografica nella misurazione della temperatura corporea superficiale del suinetto
No full textIn order to evaluate the influence of the quality of the
thermographic image on skin temperature of piglets,
1152 pictures of the back and belly from 192 subjects
were examined. Images were recorded using a FLIR
P640 camera at 37, 45 and 55 days of age. Thermal
images were analysed by software to calculate
average, minimum and maximum values of skin
temperature. The quality of the images was evaluated
subjectively by one reviewer assigning a rating of
excellent, good or sufficient on the basis of the
presence of dirt or wet skin area. Both average and
minimum skin temperatures of back and belly were
reduced significantly with decreasing quality of the
thermographic images, while the maximum value was
affected to a much lesser extent. This latter seems
more suitable for thermographic assessment of
piglets skin temperatures
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
- …
