1,720,968 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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
Transduction of cultured oligodendrocytes from normal and twitcher mice by a retroviral vector containing human galactocerebrosidase (GALC) cDNA
Krabbe disease or globoid cell leukodystropy is a lysosomal disorder caused by a deficiency of galactocerebrosidase (GALC) activity. This results in defects in myelin that lead to severe symptoms and early death in most human patients and animals with this disease. With the cloning of the GALC gene and the availability of the mouse model, called twitcher, it was important to evaluate the effects of providing GALC via a retroviral vector to oligodendrocytes in culture. After differentiation, the untransduced cells from normal mice extended highly branched processes while those from the twitcher mice did not. Oligodendrocytes in culture can be readily transduced to produce much higher than normal levels of GALC activity. Transduced normal and twitcher cells formed clusters when plated at high density. Transduction of twitcher oligodendrocytes plated at lower density, followed by differentiation, resulted in some cells having a completely normal appearance with highly branched processes. Other cells showed retraction and fragmentation. Perhaps over expression of GALC activity may be detrimental to oligodendrocytes. These studies demonstrate that the phenotype of twitcher oligodendrocytes can be corrected by providing GALC via gene transfer, and this could lead the way to future studies to treat this disease
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We 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
Significant correction of pathology in brains of twitcher mice following injection of genetically modified mouse neural progenitor cells
Krabbe disease or globoid cell leukodystrophy is an autosomal recessive disorder resulting from mutations in the galactocerebrosidase (GALC) gene. These mutations lead to deficient GALC activity, storage of substrates of the enzyme, including psychosine, death to oligodendrocytes, decreased myelination, production of globoid cells and eventually death to the individual. While most affected individuals are infants, late-onset forms are also recognized. In addition to human patients, several animal models have been well characterized, including the twitcher mouse. A spontaneously transformed progenitor cell line was isolated from an astrocyte-enriched fraction of normal mice, partially characterized and transduced with a retrovirus-containing mouse GALC cDNA to produce increased GALC activity (20-30-fold above baseline). These cells, called MAR-52, were injected into the brains of newborn affected twitcher mice. While there was only a modest increase in lifespan and body weight, there was clear evidence for the correction of the astrocytic gliosis, normal appearing oligodendrocytes and evidence for remyelination. We demonstrate that the exogenously supplied neural progenitor cells can donate GALC enzyme to oligodendrocytes in the brains of affected mice resulting in normal myelination in the area of donor cells. At this time, hematopoietic stem cell transplantation provides the best outcome in affected mice and is the only treatment available for human patients, but it does not result in a cure even when performed in asymptomatic newborns. Complete correction probably will require a combined approach to effectively treat patients with Krabbe disease. With developments in the isolation and characterization of stem cells, this approach may improve the outcome for individuals diagnosed in the future. © 2009 Elsevier Inc. All rights reserved
Author-wise bibliometric analysis based on entropy.
Author-wise bibliometric analysis based on entropy.</p
- …
