1,720,973 research outputs found
Maternal plasma mRNA species in fetal heart defects: a potential for molecular screening
No full textObjective: To verify the hypothesis that aberrant placental mRNA genes related to cardiogenesis can be detected in maternal plasma at the second trimester of pregnancy. Methods: NanoString technology was used to identify aberrant genes, comparing 39 women carrying a fetus with a congenital heart defect (CHD) to 31 controls at 19–24 weeks of gestation. The genes with differential expression were subsequently tested using real time polymerase chain reaction. Linear discriminant analysis (LDA) was used to combine all the mRNA species with discriminant ability for CHD. A multivariable receiver operating characteristic (ROC) curve having the estimated discriminant score as an explanatory variable was generated. Results: Six genes with differential expression, namely FALZ, PAPP-A, PRKACB, SAV1, STK4 and TNXB2, were found. The ROC curve yielded a detection rate of 66.7% at a false positive rate of 10%. A higher discriminant score (>75th centile) was reached for 14 CHD cases (82.4%) and only 1 control (5.8%). Two cases (11.8%) of heart rhythm disorders also yielded a discriminant score value >75th centile. Conclusion: These data represent a step forward in the screening of CHDs. Additional studies are needed to detect more mRNAs with discriminant ability and to move the first trimester screening
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
Levels of Circulating mRNA for the Tenascin-X (TNXB) Gene in Maternal Plasma at the Second Trimester in Pregnancies with Isolated Congenital Ventricular Septal Defects
No full textObjective: Maternal plasma is a source of circulating placental nucleic acids. In this study, we validated previous observations on abnormal levels of circulating messenger RNA (mRNA) for the tenascin-X gene in pregnancies with ventricular septal defects in the second trimester of pregnancy. Methods: This was a bicentric retrospective study conducted from March 2016 to July 2017. Real-time polymerase chain reaction was used to identify abnormally expressed genes, comparing ten women carrying a euploid fetus with ventricular septal defects to 30 controls at 19–24 weeks of gestation. The univariable analysis was used to determine whether the mean mRNA for the tenascin-X gene values would differ from the expected values for the controls. Results: mRNA for tenascin-X gene values was higher in ventricular septal defects, 4.38 ± 3.01 versus 1.00 ± 0.80. The result was still significant even after adjustment for gestational age. Conclusions: These data confirm previous studies on the specific association of mRNA species and type of congenital heart defect and confirm that ventricular septal defects are associated with abnormal mRNA for the tenascin-X gene. The positive predictive value of this molecular marker in the general population should be assessed through prospective studies
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
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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