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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
il-1 gene complex polymorphisms in systemic sclerosis patients with severe restrictive lung physiology
No full textSerotonin-2A receptor single nucleotide polymorphisms (SNPs) in Italian patients with systemic sclerosis
No full textT-889C IL-1α promoter polymorphism influences the response to oral cyclophosphamide in scleroderma patients with alveolitis
No full textCyclophosphamide (CYC) is the cornerstone of the treatment of systemic sclerosis (SSc)-associated fibrosing alveolitis (FAS. Despite treatment with CYC, in a not negligible proportion of SSc-FAS patients, deterioration in lung function can be observed. Interleukin-1 (IL-1) cluster gene single nucleotide polymorphisms (SNPs) were implicated in the pathogenesis of some interstitial lung diseases and may favor the progression of restrictive lung disease in SSc. The present retrospective case-control study was conducted on 18 SSc patients previously treated with oral CYC (2 mg/kg) and medium-dose steroids (prednisone 25 mg for 3 months and then tapered to 5 mg/day) for the presence of FAS-defined as the presence of areas of ground-glass attenuation on high-resolution computed tomography (HRCT) and a recent deterioration in lung function. The T/C substitution at position -889 of the IL-1alpha promoter gene (T-889C) was determined by polymerase chain reaction and restriction length fragment analysis. Patients carrying the T allele showed a significant decrease in forced vital capacity (FVC) values after 12 months of therapy (2.46+/-1.09 vs 2.59+/-1.17 l), while wild-type patients showed an increase in FVC values (2.73+/-0.54 vs 2.54+/-0.5 l) (p=0.005 between the two groups, analysis of variance for repeated measures. Patients with the T-889C polymorphism presented higher baseline erythrocyte sedimentation rates (ESR) compared to wild-type patients (50.3+/-25.4 vs 23.3+/-17.7 mm/h. Baseline ESR inversely correlated with the variation of FVC (DeltaFVC) after 12 months of therapy (r=-0.50 and p<0.05). The two groups were otherwise similar with respect to autoantibodies, age, disease duration, disease subset, radiological HRCT grade, and baseline lung physiology. The T-889C polymorphism represents a marker for worse functional responses to CYC in SSc-FAS. The mechanisms by which this SNP may negatively influence the response to CYC therapy are unknown, but might be linked to increased inflammatory responses in the lungs
Proximal interleukin-10 gene polymorphism in italian patients with systemic sclerosis
No full textInterleukin-10 (IL-10) can favour the development of fibrosis by promoting a relative shift towards T helper 2 responses. Three single base pair substitutions in the 5′ flanking region of the IL-10 gene (G/A -1082, C/T -819 and C/A -592) influence the amount of IL-10 secreted in cell cultures: the GCC haplotype is associated with an increased production, while the ACC and the ATA haplotypes are associated with intermediate and decreased production. Accordingly, three phenotypes have been individuated: high producers (GCC +/GCC +), medium producers (GCC +/GCC -) and low producers (GCC -/GCC -). We hypothesised that IL-10 haplotypes and genotypes are differently expressed in patients with systemic sclerosis (SSc) with the limited cutaneous SSc (lcSSc) subset or the diffuse cutaneous SSc (dcSSc) subset. One hundred and sixty-one unrelated Italian patients with SSc and 94 controls have been included. Their DNA was extracted and stored before being analysed by polymerase chain reaction with sequence-specific primers. The GCC haplotype is overrepresented in patients with SSc; subjects with dcSSc were the primary contributors to these results (dcSSc: 52.2% vs controls: 37.2%; χ 2 = 8.519, 2 d.f., corrected P = 0.04). In Scl70-positive patients, the GCC haplotype increased the likelihood of presenting the dcSSc subset [χ 2 = 12.56, P < 0.0005; odds ratio (OR) = 3.89, 95% confidence interval (CI 95) = 1.69-9.08]; these results were confirmed at the phenotypic level (χ 2 = 11.67, 2 d.f., P = 0.003). In Scl70-positve patients, the high-producing phenotype was associated with poor survival, independently from disease subset and gender (hazard ratio = 9.9, CI 95 = 1.6-61.27, P < 0.05). The IL-10 haplotype and genotype associated with high IL-10 production may alter the susceptibility to SSc and/or its expression, increasing the prognostic value of other well-known markers of disease severity
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
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