1,720,982 research outputs found
Physical Exam Indicated Cerclage in Twin pregnancy: a Randomized Controlled Trial
Full text linkBackground: Twin pregnancies with dilated cervix in the second trimester are at increased risk of pregnancy loss and early preterm birth; currently there is no proven therapy to prevent preterm birth in this group of women.
Objective: To determine if physical exam indicated cerclage reduces the incidence of preterm birth in asymptomatic women with twin gestations and cervical dilation diagnosed before 24 weeks of pregnancy.
Study design: Multicenter, parallel-group, open-label, randomized controlled trial of women with twin pregnancy, and asymptomatic cervical dilation from 1-5 cm between 16 0/7 to 23 6/7 weeks were enrolled from 7/2015 to 7/2019 in 8 centers. Eligible women were randomized in a 1:1 ratio to either cerclage or no cerclage. We excluded women with: monochorionic-monoamniotic pregnancy, selective fetal growth restriction, twin-twin transfusion syndrome, major fetal malformation, known genetic anomaly, placenta previa, signs of labor, or clinical chorioamnionitis. The primary outcome was the incidence of preterm birth <34 weeks. Secondary outcomes were preterm birth <32, <28 and <24 weeks, interval from diagnosis to delivery, and perinatal mortality. Data were analyzed as intention to treat.
Results: After an interim analysis was performed, the Data Safety Monitoring Board recommended stopping the trial due to significant decrease of perinatal mortality in the cerclage group. We randomized 34 women, four were excluded due to expired informed consent. Seventeen women were randomized to physical exam indicated cerclage and 13 women to no cerclage. Four women randomized to cerclage did not receive the surgical procedure, while no women in the no cerclage group received cerclage. Maternal demographics were not significantly different. All women in the cerclage group also received indomethacin and antibiotics. When comparing cerclage vs no cerclage group, the incidence of preterm birth <34 weeks was significantly decreased: 12/17 (70%) vs 13/13 (100%) (RR: 0.71 95% CI 0.52-0.96), as well as preterm birth <32 weeks 11/17 (64.7%) vs 13/13 (100%) (RR: 0.65 95% CI 0.46-0.92), preterm birth <28 weeks 7/17 (41%) vs 11/13 (84%) (RR: 0.49 95% CI 0.26-0.89) and preterm birth <24 weeks 5/17 (30%) vs 11/13 (84%) (RR: 0.35 95% CI 0.16-0.75). The mean gestational age at delivery was later: 29.05±1.7 vs. 22.5±3.9 weeks (p<0.01); the mean interval from diagnosis of cervical dilation to delivery was longer: 8.3±5.8 vs. 2.9±3.0 weeks (p=0.02). Perinatal mortality was also significantly reduced in the cerclage group 6/34 (17.6%) vs 20/26 (77%), (RR: 0.22 95% CI 0.1-0.5).
Conclusion: A combination of physical exam indicated cerclage, indomethacin, and antibiotics in asymptomatic twin pregnancies before 24 weeks significantly decreases preterm birth at all evaluated gestational ages. Most importantly, cerclage in this population is associated with a 50% decrease in very early preterm birth <28 weeks and with a 78% decrease in perinatal mortality
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
Randomized controlled trial of prolonged second stage: extending the time limit vs usual guidelines.
Full text linkBACKGROUND: Guidelines for management of the second stage have been proposed since the 1800s and were created largely by expert opinion. Current retrospective data are mixed regarding differences in maternal and neonatal outcomes with a prolonged second stage. There are no randomized controlled trials that have evaluated whether extending the second stage of labor beyond current American College of Obstetricians and Gynecologists recommendations is beneficial.
OBJECTIVE: The purpose of this study was to evaluate whether extending the length of labor in nulliparous women with prolonged second stage affects the incidence of cesarean delivery and maternal and neonatal outcomes.
STUDY DESIGN: We conducted a randomized controlled trial of nulliparous women with singleton gestations at 36 0/7 to 41 6/7 weeks gestation who reached the American College of Obstetricians and Gynecologists definition of prolonged second stage of labor, which is 3 hours with epidural anesthesia or 2 hours without epidural anesthesia. Women were assigned randomly to extended labor for at least 1 additional hour, or to usual labor, which was defined as expedited delivery via cesarean or operative vaginal delivery. The exclusion criteria were intrauterine fetal death, planned cesarean delivery, ageyears, and suspected major fetal anomaly. Primary outcome was incidence of cesarean delivery. Maternal and neonatal outcomes were compared secondarily. Statistical analysis was done by intention-to-treat.
RESULTS: Seventy-eight nulliparous women were assigned randomly. All of the women had epidural anesthesia. Maternal demographics were not significantly different. The incidence of cesarean delivery was 19.5% (n = 8/41 deliveries) in the extended labor group and 43.2% (n = 16/37 deliveries) in the usual labor group (relative risk, 0.45; 95% confidence interval, 0.22-0.93). The number needed-to-treat to prevent 1 cesarean delivery was 4.2. There were no statistically significant differences in maternal or neonatal morbidity outcomes.
CONCLUSION: Extending the length of labor in nulliparous women with singleton gestations, epidural anesthesia, and prolonged second stage decreased the incidence of cesarean delivery by slightly more than one-half, compared with usual guidelines. Maternal or neonatal morbidity were not statistically different between the groups; however, our study was underpowered to detect small, but potentially clinical important, differences
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
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
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