1,721,002 research outputs found
MICROPERIMETRIA E RIABILITAZIONE VISIVA
Lo studio funzionale microperimetrico permette un approccio più completo alla valutazione delle maculopatie, non solo dal punto di vista diagnostico, ma nel follow-up terapeutico. Appare inoltre fondamentale il ruolo che la microperimetria svolge e svolgerà nel programma riabilitativo dei soggetti ipovedenti
Microperimetry in low vision: 2 hours course "International symposium on low vision rehabilitation and visual ability", Rome 10- 12 March 2005, 12 March 2005
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
Morphologic differences, according to etiology, in pigment epithelial detachments by means of en face optical coherence tomography
PURPOSE:
To assess morphologic differences in pigment epithelial detachment (PED) with en face optical coherence tomography in central serous chorioretinopathy (CSC) and age-related macular degeneration (AMD).
METHODS:
We recruited 30 eyes of 22 patients with PED. Nine eyes had a clinical diagnosis of CSC and 21 had AMD. All patients were assessed with en face optical coherence tomography. Morphologic PED aspects were estimated on C-scans and classified according to shape, inner silhouette, content, wall aspects, wall thickness, and size.
RESULTS:
Pigment epithelial detachment shape was predominantly circular (88.8%) in CSC and irregular or with multilobular features in AMD (76.2%). The PED inner silhouette had a smooth aspect (88.9%) in CSC and a slightly granular aspect or granular profile in AMD (100%). Clear PED content was the most characteristic feature of CSC (88.9%) but not of AMD. In CSC, PED morphologic wall aspect was uniform or slightly irregular (100%), while in AMD, it was slightly irregular (52.4%) or irregular (47.6%). Pigment epithelial detachment wall thickness and dimensions were larger in AMD than in CSC. Statistically significant differences were observed between CSC and AMD concerning PED inner silhouette, contents, wall aspects, and wall thickness measurements.
CONCLUSION:
En face optical coherence tomography scanning is a valuable tool for showing important morphologic differences between CSC and AMD
Dispelling the Myths Behind First-author Citation Counts
We 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
Observed positive correlation between Epstein-Barr virus infection and focal choroidal excavation.
PURPOSE: To evaluate a possible correlation between focal choroidal excavation and Epstein-Barr virus (EBV) infection.
METHOD: Three eyes of three patients underwent a comprehensive ophthalmologic examination including visual field testing, color fundus photography, optical coherence tomography (OCT), fluorescein angiography and indocyanine green angiography. In addition, hematological and viral infectivity were also evaluated.
PATIENTS: Two females and one male with a mean age of 53.6 ± 5.6 years were studied.
RESULTS: In all patients, both the anterior and posterior segment evaluations were unremarkable except for the presence of a spot with focal retinal pigment epithelium (RPE) alteration. In patients 1 and 2, OCT disclosed a normal neuroretinal structure above the lesion and a focal 'punch-out' choroidal lesion with total absence of the RPE coupled with a localized hyporeflectivity in the subretinal space. In two of the three patients, OCT showed normal outer retinal layers, including the photoreceptor layer and the external limiting membrane with a hyporeflective space under the inner segment/outer segment (IS/OS) junction. In one patient, the retinal structure appeared to descend down into the choroidal excavation with an absence of the IS/OS junction and RPE. Moreover, the outer retinal layers appeared to be deformed. In all three patients, the choriocapillaris and choroid showed significant defects as if 'punched out' and the scleral boundary was more evident. In all three patients, an active EBV infection was confirmed by hematological investigation.
CONCLUSIONS: In all our patients with focal choroid anomalies, such as choroidal excavation observed by OCT, a systemic infection by the EBV was detected. A larger number of similar cases are necessary to corroborate these preliminary observations
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