1,721,044 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
Evidence for a massive dark object in NGC 4350
No full textIn this work we build a detailed dynamic model for an S0 galaxy possibly hosting a central massive dark object (MDO). We show that the photometric profiles and the kinematics along the major and minor axes, including the h(3) and h(4) profiles, imply the presence of a central MDO of mass M(MDO)similar to1.5-9.7x10(8) M-., i.e. 0.3-2.8 per cent of the mass derived for the stellar spheroidal component. Models without MDO are unable to reproduce the kinematic properties of the inner stars and of the rapidly rotating nuclear gas. The stellar population consists of an exponential disc (27 per cent of the light) and a diffuse spheroidal component (73 per cent of the light) that cannot be represented by a simple de Vaucouleurs profile at any radius. The ML ratios we found for the stellar components (3.3 and 6.6 respectively) are typical of those of disc and elliptical galaxies
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
Computational morphogenesis and construction of an acoustic shell for outdoor chamber music
No full textInfluence of age on hepatic uptake of HDL1-cholesterol in male Wistar rats with bile duct cannulation.
No full textWe have shown previously that the age-dependent increase in plasma cholesterol levels observed in male Wistar rats is associated with relevant changes in the lipoprotein pattern (in particular, with a much higher proportion of the HDL1 class) that are evident in animals from the age of 9 months. In this study, the possibility that a decreased catabolism of HDL1 cholesterol may cause this is evaluated by infusing this lipoprotein fraction labeled with [C-14]cholesterol into both young (3.5+/-0.5 months) and adult (13.0+/-1.0 months) male Wistar rats with a permanent biliary drainage. The clearance of radioactivity from the blood compartment was slower in the older animals than in the younger ones. Conversely, the incorporation of radioactivity into plasma cholesteryl esters and the secretion of radioactivity into bile was higher in the younger animals. These results support the hypothesis that the age-related increase in HDL1 proportion is due, at least in part, to a slower liver catabolism of HDL1-cholesterol
Age-related changes in blood and liver lipids of male Wistar rats.
No full textThe results of this study indicate that the age-dependent plasma cholesterol increase observed in male Wistar rats is correlated with changes in both the distribution of high-density lipoprotein fractions and the storage of hepatic cholesterol. Specifically, the lipoprotein distribution showed a significant increase in the proportion of HDL1 and a symmetrical decrease in both the HDL2 and HDL3 fractions during the 3 month to 18 month age period. There were no significant changes in the very-low density and low-density lipoprotein fractions. The chemical composition of lipoproteins showed many age-related variations, especially in the proportion of cholesteryl ester and in the distribution of HDL subfractions. A study of fatty acyl composition of the major lipid classes showed that, within cholesteryl ester found in liver, there was an increase in the proportion of saturated fatty acids. Polyunsaturated fatty acids increased in the cholesteryl esters found in high-density lipoproteins of older rats. These observations suggest that the age-dependent accumulation of body cholesterol occurs by a reduced catabolism of HDL, fraction, and modifications in plasma and liver lipids
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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