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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Cardiovascular Events in Moderately to Severely Obese Obstructive Sleep Apnea Patients on Positive Airway Pressure Therapy
No full textBackground: In moderately to severely obese patients with
obstructive sleep apnea (OSA), the effects of long-term positive
airway pressure (PAP) treatment on cardiovascular risk
are poorly defined. Purpose: To assess the effect of continuous
positive airway pressure (CPAP) or noninvasive ventilation
(NIV) on the occurrence of cardiovascular events in
obese OSA patients. Methods: We performed a noninterventional
observational study in obese OSA patients recruited
between 2007 and 2010 at the Sleep Center, University of
Grenoble, treated with CPAP or NIV, and followed for 5.6
years by a single home care provider. Baseline clinical characteristics,
blood chemistry, and respiratory and vascular
function were assessed. Incident cardiovascular events were
investigated by phone interviews. Results: A total of 103 patients
(55 men, 48 women; age and body mass index [BMI] at
diagnosis 54.1 ± 10.5 years and 40.3 ± 5.5, respectively [mean
± standard deviation]; CPAP: n = 75; NIV: n = 28) agreed to
participate in the study. Grade I, II, and III obesity occurred in 17.5, 33.0, and 49.5% of the sample, respectively. In patients
using PAP treatment ( n = 69), the mean nightly use was
6.3 ± 2.4 h. Thirty-one patients stopped PAP treatment during
follow-up. Three patients on NIV died. Nonfatal cardiovascular
events ( n = 27) occurred in 19 patients, who were
older and showed higher number of comorbidities and triglyceride
levels than patients without events. In the patients
who interrupted treatment, the event rate was high and increased
with the number of comorbidities, while BMI at
baseline did not predict events. Conclusions: The study suggests
that regular PAP treatment may be associated with
protection against cardiovascular risk in obese OSA patients,
especially in the presence of multiple comorbidities
Differential effects of oncogenic H- and K-ras expression on HT-29 colorectal carcinoma cell line.
No full textThe Ras oncogene is mutated in about 30% of the human tumors and its mutations are always point mutations concerning codon 12, 13 and 61. These mutations cause in the proteins a reduced GTPase activity, so that they become constitutively active. In human cells there are three main isoforms of Ras (H, K, N-ras) which can trigger alternative pathways of signal trasduction. In order to investigate the effects of expression of different oncogenic Ras isoforms in colorectal carcinoma cells (HT-29), we obtained stable clones of HT-29 cells transfected with cDNAs codifying H-RasG12V and K-Ras G12V called respectively H12 and K12 and K-RasG13D called K13, under the control of an hormone-inducible promoter. We had previously observed changes in shape and growth rate when mutated Ras was expressed. We then analyzed the differential expression of genes such as the cell-cycle inhibitor p21 and the EMT associated gene snail. Q-RT PCR assay showed an increase in p21 level only in H12 cells but not in K13 and K12 compared with the respective controls. Instead, snail mRNA level was increased in all thre clones. We investigated also by Semiquantitative RT-PCR H-RasG12V, p21 and snail levels in H12 cells induced for a long time and we noted a decreased level of H-RASG12V associated with no p21 and snail expression. Our results show that specific mutations of different Ras isoforms have different effects on morphology and gene expression in Ht-29. Other studies are of course necessary to shed more light on the role played by Ras mutations in tumor development
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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