1,720,996 research outputs found
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
Characterization and differentiation of equine tendon-derived progenitor cells.
No full textMesenchymal stem cells have been recently investigated for their potential use in regenerative medicine. Population of adult stem cells were recently identified in human and lab animal tendons, but no detailed investigations have been made in the equine species. The aim of our study is to identify a progenitor cell population from tendon tissue (TSPCs) in the horse superficial digital flexor tendon that are able to be highly clonogenic, to grow fast and to differentiate in different induced cell lineages as well as bone marrow derived progenitor cells (BM-MSCs). The hypothesis that TSPCs possess a mesenchymal stem cell behavior opens a new prospective for tendon regenerative medicine approaches. TSPCs were expanded more rapidly and showed higher plating efficiency when compared with BM-MSCs. Both cell lines expressed identical stem cell markers in vitro and they were able to differentiate towards osteogenic and adipogenic lineages as demonstrated with cytochemical staining and mRNA gene expression. TSPCs showed a positive but limited chondrogenic differentiation compared with BM-MSCs as demonstrated by histological and biochemical analyses. According to our results, equine TSPCs have high clonogenic properties and proliferating potential, they express stem cell markers and have the capability to be multipotent as well as BM-MSCs. These findings suggest that TSPCs may represent a good model for stem cell biology and could be useful for future tendon regenerative medicine investigations
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
WHITE STRIPING APPEARANCE ALONG GROWTH ON BROILER CHICKENS TREATED WITH DIFFERENT COCCIDIOSIS CONTROL PROGRAMS
No full textWhite striping (WS) is an alteration of broiler muscle characterised by the presence of white striations parallel to the direction of muscle fibers. This condition is becoming increasingly important in broiler production because it affects the acceptance of raw meat by the consumer and its hysicochemical characteristics, thus decreasing the economic value (1). In this study the age of WS onset in broiler chickens and the effect of diet and of different coccidiosis control programs on WS prevalence at slaughter, were evaluated.
Four groups of 180 chickens were randomly allotted to four experimental treatments: control (C), coccidiostat (Cox), vaccinated (V), and vaccinated fed with a low energy diet (VLE). The birds were weighed at 12, 25, 42, and 51 d of age. Twenty animals per treatment were sacrificed at 12 and 25 d of age, whereas the remaining chickens at 51 d. Breasts were categorized based on the degree of WS following the lesion score proposed by Kuttappan et al. (2): 0=absence (normal breast), 1=moderate (breast with white lines less than 1 mm thick), 2=severe (breast with white lines more than 1 mm thick). For histological evaluation, up to now 34/80 (d 12) and 46/80 (d 25) breast samples were examined.
At 12 d of age all breasts were classified as normal (WS score 0), whereas at 25 d of age WS was macroscopically evident with score 1 in a limited number of birds (3/20 group C, 2/20 group Cox, 3/20 group V, 1/20 group VLE).
Histologically, myopathic changes were found in 29/34 (85%) of samples at d 12, and 46/46 (100%) of samples at d 25. At d 12, breast muscles were affected by fiber size change, and multifocal mild degeneration/necrosis, while at d 25 these alterations were increasingly severe and associated with heterophilic and macrophagic infiltration, early interstitial fibrosis, and fat infiltration.
The absence of macroscopic lesions at d 12 associated with the presence of early and mild histological lesions in some samples indicates the onset of WS around 12 d.
At 51 d of age the prevalence of WS was above 90% in all groups, and the prevalence of WS score 2 was 77.6%, 64.4%, 62.6% and 61.6%, for Cox, VLE, V and C, respectively, being significant (P<0.001) the difference Cox vs V and C.
The coccidiostat effect on the increase in WS severity seems attributed to the higher initial birds’ growth.
This study provided a new perspective for the control of WS prevalence and a starting point for further studies.
REFERENCES
1. Kuttappan, V. A., V. B. Brewer, P. W. Waldroup, and C. M. Owens. 2012. Influence of growth rate on the occurrence of white striping in broiler breast fillets. Poult. Sci. 91:2677–2685.
2. Kuttappan, V. A., H. L. Shivaprasad, D. P. Shaw, B. A. Valentine, B. M. Hargis, F. D. Clark, S. R. McKee and C. M. Owens. 2013. Pathological changes associated with white striping in broiler breast muscles. Poult. Sci. 92:331-338
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
- …
