1,721,005 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
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
BALB-neuT Female Mice as a Dynamic Model of Mammary Cancer
No full textTumor-transplanted rodents are primarily adopted to study cancer
progression in vivo and the inhibitory potential of the immune system. Genetically engineered, cancer-prone mice, however, more closely mimic several features of human cancer. Inbred BALB/c female mice transgenic for the rat neu (Her-2/neu, ErbB-2) oncogene (BALB-neuT mice) constitute an intensively studied mammary cancer model.
Key features of this model include that (1) each of their ten mammary glands develops an independent carcinoma that slowly progresses from microscopic lesions to invasive tumors; (2) multiple in situ carcinomas are accompanied by greater dissemination of neoplastic cells into the bone marrow; (3) lung metastases are evident in the later stages; (4) over-expression of the protein product of the transgenic neu oncogene in the
newborn thymus induces the deletion of T cell clones reacting with high-affinity against it, while the step-wise progression of mammary lesions triggers negative regulation mechanisms that suppress antibody- and perforin-mediated immune surveillance
mechanisms. Thus, boosts of innate immunity delay cancer progression and vaccines administered when only early microscopic lesions are present provide lifelong protection, whereas their efficacy tails off when they are administered to mice with more advanced lesions. Because this model mimics some of the most critical features of human disease, it has been successfully used to investigate a number of therapeutic
agents, including the role of adaptor proteins (P130 cap), signal transducers (STAT3), phosphoinositide 3-kinase (PI3K), and oncogenic stress sensing kinases (MKK7) in neu-driven carcinogenesis, and assessment of the efficacy of braki therapy in the control of mammary cancer
Microarray data analysis and mining
No full textDNA microarray is an innovative technology for obtaining information on gene function. Because it is a high-throughput method, computational tools are essential in data analysis and mining to extract the knowledge from experimental results. Filtering procedures and statistical approaches are frequently combined to identify differentially expressed genes. However, obtaining a list of differentially expressed genes is only the starting point because an important step is the integration of differential expression profiles in a biological context, which is a hot topic in data mining. In this chapter an integrated approach of filtering and statistical validation to select trustable differentially expressed genes is described together with a brief introduction on data mining focusing on the classification of co-regulated genes on the basis of their biological function
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