1,721,121 research outputs found
Gli omologhi dei geni Sex-lethal and doublesex di Drosophila melanogaster in Ceratitis capitata: parziale conservazione evolutiva di una gerarchia di regolazione genica della determinazione del sesso
No full textSono stati isolati e caratterizzati gli omologhi dei geni di Drosophila melanogaster doublesex e Sex-lethal in Ceratitis capitata, detta mosca mediterranea che causa importanti danni all'agricoltura in svariati paesi nel mondo. I due geni svolgono funzioni chiave nella determinazione del sesso e differenziamento sessuale di Drosophila, ed inoltre sono organizzati in una cascata regolativa che vede Sex-lethal a monte di doublesex. In Ceratitis capitata è stata evidenziata un conservazione strutturale di entrambi ma regolativa/funzionale del solo doublesex
Appendectomy in children with hypercalciuria/hyperuricosuria
Full text linkRecurrent abdominal pains (RAPs) represent a common problem in
children sometimes leading to unnecessary and invasive procedures. The rates of appendectomy were evaluated consecutively in 180 children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAPs, and in 270 control subjects.
Of the HC/HU patients 10% and of controls 1.5% underwent appendectomy
(p!0.0001). In 15 out of 18 HC/HU patients appendectomized, RAPs persisted with the same frequency and severity after the operation; 10 out of 18 had dysuria and/or gross hematuria 2 dayse12 months after appendectomy. At our first visit,urinalysis was negative for hematuria in 13 out of 18 patients and in eight out of the
10 with a previous history of dysuria or gross hematuria. Pain recurrences resolved or improved in nine out of the 11 patients followed at least 1 year after general or specific therapy for HC/HU.
The inconstant association of dysuria and hematuria with RAPs in children with HC/HU may lead to the urological origin of pain being overlooked, and may explain the high rate of appendectomy among these children. The possibility of HC/HU therefore should be taken into account in children with RAPs even when dysuria and hematuria are not present
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
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