1,721,186 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
P12.13: Reproducibility and clinical relevance of antenatal detection of arterio-arterial anastomoses by Doppler placental assessment in monochorionic twin pregnancies
No full textObjectives: To evaluate the reproducibility of Doppler antenatal
detection of arterio-arterial anastomoses (AAA) in monochorionic
twin pregnancies in a centre other than where this method was first
systematically applied and to correlate the prenatal identification of
AAA with the clinical outcome of these pregnancies.
Methods: 21 monochorionic diamniotic twin pregnancies and
one dichorionic triamniotic triplet seen at the Twin Clinic at
the University of Brescia were recruited prospectively (October
2002–February 2003). After routine ultrasonographic assessment,
AAA were searched using Color or Power and spectral Doppler. The
presence of AAA was confirmed postnatally by placental injection
studies. Data on the presence of AAA obtained from injection studies
were compared with Doppler findings to establish sensitivities and
specificities of prenatal Doppler investigation. Clinical outcome
of the two groups (with or without AAA detected in utero)
were compared.
Results: Data of 19 patients were available for the analysis. AAA
were detected in 12 cases (63%) antenatally and in 16 (84.2%) at
injection study. Sensitivity and specificity of Doppler for detecting
AAA were 75% and 100% respectively. Detection rates increased
at advanced gestations and with anterior/fundal placentae. The
incidence of twin–twin transfusion syndrome (TTTS) was higher in
the group with no AAA detected in vivo compared to the group with
AAA found with Doppler (28.6% vs 16.6%), but not statistically
significant (P = 0.5). All TTTS cases with an AAA found in utero,
regressed spontaneously or after one amnioreduction. All cases with
a birthweight discordance > 20% and no signs of TTTS, had an
AAA detected with Doppler and showed intermittent absent/reverse
diastolic flow in the umbilical artery of the smaller twin.
Conclusion: This study confirmed the reproducibility and clinical
relevance of AAA Doppler detection in vivo in monochorionic
pregnancies
P369: Ultrasound cervical length to predict spontaneous preterm delivery in twin pregnancies
No full textObjective: To analyse the predictive value of different cervical length
cut-offs for spontaneous preterm delivery <32 and <34 weeks in
twin pregnancies.
Methods: Transvaginal cervical ultrasound examinations were
performed in 106 twin pregnancies between 20 and 26.6 weeks
(January 2001 to January 2003). Sensitivity, specificity and
predictive values of cervical length (20, 25 mm) at 20–24 and
24.1–26.6 weeks for the prediction of spontaneous preterm birth
<32 and <34 weeks were calculated. Twin gestations electively
delivered preterm because of maternal or fetal indications were
excluded from this analysis.
Results: The median gestational age at delivery was 35 weeks (range
23.2–39.3). Cerclage was performed in 12 patients with cervical
length 25 mm or prolapse of membranes at a median gestational age
of 23 weeks (range 20.5–26.2). The rate of spontaneous delivery
<32 and <34 weeks was 8.4% (9/106) and 13.2% (14/106)
respectively. In the group of patients evaluated at 20–24 weeks,
7/85 (8.2%) women delivered spontaneously <32 weeks and
9/85 (10.6%) <34 weeks; in the group of patients evaluated at
24.2–26.6 weeks, 2/66 (3%) delivered spontaneously <32 weeks
and 7/66 (10.6%) <34 weeks. Cervical length at 20–24 weeks
with a cut-off value 20 mm had specificities of 99% and 99%,
sensitivities of 43% and 33%, negative predictive values of 95%
and 92%, positive predictive values of 75% and 75% for delivery
<32 and <34 weeks, respectively. Cervical length at 20–24 weeks
with a cut-off value 25 mm had specificities of 95% and 94%,
sensitivities of 43% and 33%, negative predictive values of 95%
and 91%, positive predictive values of 43% and 43% for delivery
<32 and <34 weeks, respectively.
Conclusions: In twin gestations a cervical length 20 mm measured
at 20–24 weeks is the best cut-off to predict spontaneous
preterm delivery
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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