1,720,957 research outputs found
Caseous Calcification of the Mitral Annulus Associated with Severe Mitral Regurgitation: A Multimodality Diagnostic Approach
Full text linkCaseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification, and a multimodality approach is advised to ensure an accurate diagnosis. We report a case of a patient with CCMA, associated with severe mitral regurgitation. An 82-year-old woman was admitted due to worsening heart failure. Transthoracic echocardiography revealed a fixed, hyperechogenic mass, accompanied by restriction of the posterior mitral leaflet, and subsequent severe mitral regurgitation. Transesophageal echocardiography demonstrated a restricted motion of the posterior mitral leaflet, because of a large, echogenic mass (15 mm × 11 mm), attached to the mitral annulus, vacuolated with a central echolucent aspect, lacking acoustic shadowing. Contrast-enhanced cardiac computed tomography identified a distinct oval mass (18 mm × 11 mm × 19 mm) presenting a central hypodense content and peripheral calcification, strongly suggestive of CCMA. Considering the patient’s profile, surgical valvular replacement was considered unsuitable. Therefore, a transcatheter edge-to-edge repair was performed, resulting in mild residual regurgitation
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
Dynamic changes in pericoronary fat attenuation index predict cardiac allograft vasculopathy (CAV) progression and clinical and radiological outcomes in heart transplant recipients: a pilot study
No full textreservedIntroduzione: Evidenze consistenti supportano l’utilizzo dell’indice di attenuazione del grasso pericoronarcio (pFAI) come biomarcatore di infiammazione coronarica e predittore prognostico nei pazienti sottoposti a trapianto cardiaco (TC). La valutazione del pFAI può essere condotta considerando il tratto prossimale del vaso, ovvero i primi 40 mm di lunghezza (pFAI prossimale), oppure l’intera lunghezza del vaso dall’ostio sino alla sua porzione distale (pFAI pancoronarico) delle tre coronarie epicardiche principali. Inoltre è possibile quantificare il pFAI a livello di placca coronarica (pFAI di placca). Lo scopo dello studio è indagare se la valutazione del pFAI mediante angio-TAC coronarica sia in grado di predire un peggioramento del grado di vasculopatia del graft cardiaco (CAV) o l’incidenza di eventi clinici in una coorte di pazienti sottoposti a TC. Metodi: Il pFAI prossimale, pancoronarico e di placca è stato valutato retrospettivamente in una coorte di 86 pazienti sottoposti a TC, sia al baseline [mediana: 6,9 anni (IQR 4,9–13) post-trapianto], sia al follow-up mediante angio-TAC coronarica [mediana: 2,1 anni (IQR 2,0–2,2) dopo il baseline]. I valori dei 3 pFAI sono stati confrontati tra sottogruppi e tra i due timepoint utilizzando il test U di Mann–Whitney per confronti indipendenti e il test di Wilcoxon per confronti appaiati. L’incidenza degli eventi clinici e radiologici è stata analizzata mediante test esatto di Fisher e test di McNemar. La capacità predittiva del pFAI è stata esaminata tramite modelli di regressione logistica univariata e multivariata. Risultati: Nei soggetti con progressione radiologica della CAV al follow-up (secondo classificazione ISHLT), i valori di pFAI prossimale hanno mostrato un incremento significativo nel tempo. Le misurazioni medie e mediane del pFAI prossimale hanno avuto performance simili, così come quelle del pFAI pancoronarico. Nel sottogruppo di pazienti che ha sviluppato eventi clinici compositi sia il pFAI prossimale che pancoronarico hanno evidenziato un incremento progressivo e statisticamente significativo rispetto al baseline. Tale associazione è rimasta significativa anche dopo aggiustamento per variabili confondenti [OR multivariata per incremento di 10 HU: 7,35; IC 95%: 1,1–48,9; p = 0,039]. Il rapporto dinamico del pFAI prossimale (baseline/follow-up) è risultato significativamente più elevato nei soggetti con peggioramento radiologico e/o clinico [OR multivariata per incremento di 0,1: 26; IC 95%: 1,51–447; p = 0,025]. L’utilizzo del cut-off di −70,1 HU non ha permesso tuttavia di identificare sottogruppi associati a un rischio significativamente aumentato di eventi clinici o radiologici. A livello di coorte complessiva, le misurazioni statiche del pFAI non hanno discriminato la presenza o assenza di CAV. Conclusioni: pFAI prossimale e pancoronarico si confermano potenziali marcatori dell’attività globale della CAV nel contesto del trapianto cardiaco. Le valutazioni statiche e dinamiche del pFAI possono contribuire all’identificazione della CAV attiva, indipendentemente dalla visualizzazione diretta delle placche, e rappresentare uno strumento predittivo di eventi avversi nei pazienti sottoposti a TC
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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