1,721,035 research outputs found
Pediatric isolated fallopian tube torsion
No full textIsolated fallopian tube torsion (IFTT) is an isolated rotation of the fallopian tube around itself, without torsion of the ovary. The incidence of fallopian tube torsion is one in 1,500,000 adults. IFTT is less frequent in children and teenagers then in adults, but the real incidence in pediatric patients is difficult to determine, because rarely reported in the literature. IFTT generally occurs as adnexal torsion caused by a concomitant ovarian pathology. In adult age several intrinsic or extrinsic predisposing factors have been identified leading to IFTT while in the pediatric age group the possible factors are preexisting congenital malformations such as hydrosalpinx (HSX). Primary causes are anatomical, such as abnormality of length, mobility and structure. Secondary causes are acquired including infections, adhesions, endometriosis and neoplasms. Both primary and secondary causes are likely to be responsible for pediatric tubal disease. IFTT is a rare cause of abdominal pain often presents with aspecific abdominal pain (acute or chronic). Diagnosis appears difficult to obtain with standard diagnostic procedures and in most patients a definitive diagnosis is obtained only through a surgical exploration. Operative procedures range from salpingectomy to conservative management with de-torsion of the tube unless there is evidence of necrosis or rupture. However, surgical remedy of the torsed tube is controversial. This chapter reports common presenting signs, symptoms, and radiological findings as well different surgical options available and adopted, focusing on the current management and the preservation of fertility in these young patients with this rare pediatric entity
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
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
Chiral Iron Complexes in Asymmetric Organic Transformations
No full textTransition metal chiral catalysts can feature metal stereocenters in different coordination geometries. In the case of iron, both octahedral and tetrahedral geometries possessing a chirotopic iron atom have been synthesized and tested in stereoselective organic transformations. The configurational stability of these complexes, which in some cases is hampered by decomplexation and recomplexation of labile ligands, is achieved by the use of multidentate ligands in octahedral complexes, and of cyclopentadienyl anions (half sandwich complexes) in the case of tetrahedral structures. The use of octahedral iron complexes featuring configurationally stable iron stereocenters is reviewed in highly enantioselective reductions (hydrogenation and transfer hydrogenation of ketones) and oxidations (cis-dihydroxylation of alkenes, epoxidation, sulfoxidation), while the use tetradentate iron complexes is described in C−C bond-forming reactions and reductions. (Figure presented.)
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