1,721,036 research outputs found
Wefare implications of artificial rearing and early weaning in sheep
No full textSoon after parturition a lasting and mutual ewe–lamb bond is established. However, in an increasing
number of intensive sheep farms, lambs are separated from the dam at an early age. When artificial
rearing is applied lambs are often kept with mothers for 2 days to allow the ingestion of maternal
colostrum and then abruptly removed from their dams. Thus, lambs experience a marked emotional
stress represented by the loss of the most relevant social model at this early stage of their behavioural
development and a nutritional stress represented by the transition from maternal milk to a commercial
milk substitute. These animals when exposed to open field tests show reduced levels of vocalization,
are slower to initiate movements, spend less time in ambulatory behaviour and display an increased
cortisol response than non-separated animals. In addition, artificial rearing performed on lambs
from 2 days of age onward can cause decreased cellular and humoral immune responses. The main
oral abnormal behaviour performed by artificially reared lambs is represented by sucking the navel
or the scrotum of pen mates. This activity is evident from the initial days on reconstituted milk and
lasts until weaning from milk. Attempts have been made to reduce the detrimental effects of early
separation. Some of them mainly focus on the emotional aspects (it is recommended not to leave a lamb
alone for artificial rearing), others aim at reducing the nutritional impact of artificial rearing (milk
intake can be increased by offering a mix of ewe milk and a milk replacer during the first week and then
gradually moved to a diet based only on milk substitute which results in higher growth rates). As
compared with artificial rearing, early weaning performed at 3 months of age is associated with a later
disruption of the mother–young bond and the consequent direct replacement of maternal milk by solid
food. However, when they are given the chance, ewes and their lambs form long-term social associations which exceed the age of natural weaning, regarded as the end of the milk feeding period.
Early weaned lambs emit an increased number of high pitched bleats immediately after weaning than
before and this increment is still evident 2 days afterwards. Neither partial nor gradual separation from
mothers is able to reduce the stress associated with early weaning. In conclusion, premature separation
from mothers has clear and marked detrimental effects on various functions in lambs. For lambs
maternal deprivation seems to be worse at 2 days (artificial rearing) than at 3 months of age (early
weaning)
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
- …
