1,720,963 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    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

    National Institutes of Health stroke scale score at admission can predict functional outcomes in patients with ischemic stroke undergoing carotid endarterectomy

    No full text
    Objective: The aim of present study was to evaluate the prognostic effect of the National Institutes of Health stroke scale (NIHSS) score for patients who had undergone acute carotid endarterectomy (CEA) and assess the clinical and morphologic factors that could predict for worse outcomes. Methods: The data from 183 consecutive patients who had undergone CEA after ischemic stroke were analyzed from January 2015 to January 2021. The patients were divided into two groups using the NIHSS score cutoff of 4. Functional dependence was assessed at hospital discharge and 90 days after discharge. Results: Of the 183 patients, 102 (55.7%) had had a minor stroke (group A; NIHSS score of ≤4) and 81 (44.3%) had had a moderate to major stroke (group B; NIHSS score >4). Groups A and B showed significant differences in their intracranial anatomic features, including the presence of an incomplete circle of Willis (7.8% vs 17.3%; P = .05), cerebral ischemic lesion volume ≥4000 mm3 (5.9% vs 24.7%; P ≤ .001), and a high Alberta stroke program early computed tomography score of 8 to 10 (75.5% vs 44.4%; P ≤ .001). The overall rate of combined perioperative stroke, myocardial infarction, and death was 1.1%, with no strokes recorded during the interval to CEA. Patients in group A had a lower rate of functional dependence at discharge (4.9% vs 35.8%; P ≤ .001) and at 90 days after the index stroke event (2.5% vs 19.6%; P ≤ .001) compared with those in group B. Using multivariate binary logistic regression, an admission NIHSS score >4 was significantly associated with higher odds of functional dependence at discharge (odds ratio, 7.9; 95% confidence interval, 2.7-18.5; P ≤ .001) and at 90 days (odds ratio, 10.4; 95% confidence interval, 2.7-19.3; P = .002). Conclusions: An NIHSS score >4 at admission increased the risk of a higher modified Rankin scale score at both hospital discharge and 90 days after the index stroke event. Acute CEA was safe and feasible for patients with ischemic stroke, even if they had previously undergone intravenous thrombolysis

    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 link
    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

    Sheath-Anchoring for Rail Guidewire Technique to Advance and Deploy Thoracic Endograft in Hostile Anatomy

    No full text
    Background: To describe a bailout technique to advance and precisely deploy thoracic endograft in the ascending aorta in case of difficulty crossing the aortic arch. Case Reports: A 73-year-old man presented with a large ruptured aneurysms in the descending aorta. During the TEVAR, stent-graft passage through the aortic arch was impossible due to the severe tortuosity of the aorta. The problem has been resolved using the sheath-anchoring rail guidewire (SARG) technique. Results: Through an axillary access, a snare was used to capture the stiff wire from the femoral access. A sheath was advanced over the stiff wire to the ascending aorta and placed there. By exploiting the grip of the sheath on the stiff in the ascending aorta, it was possible to handle the tension, move the delivery system through the arch and carefully deploy the graft. Conclusion: The SARG is a simple and quick learning technique which can be useful for Physicians dealing with complex aortic arch anatomy

    Bridging Stents in Fenestrated and Branched Endovascular Aneurysm Repair: A Systematic REVIEW

    No full text
    Background: Concern exists about durability of stent grafts used to bridge aortic grafts to visceral and renal arteries during fenestrated and branched endovascular aneurysm repair (F/B-EVAR). There are no guidelines regarding the ideal technique for joining target vessels (TVs). Methods: We systematically reviewed data published from 2014 to 2019 using PRISMA guidelines and PICO models. Keywords were searched in MEDLINE, EMBASE, and Cochrane Library. All articles were screened by two authors (a third author in case of discrepancies). Only original articles regarding F/B-EVAR in complex aortic aneurysm, reporting the number and type of TVs mated, the onset of bridging stent complications, and reinterventions on TVs were included. Analysis included quality assessment scoring, types of stent grafts, and complications related to bridging stents. Results: 19 studies were included with 2,796 patients and 9556 TV; 4,797 renal arteries (50.2%), 4,174 visceral arteries (43.6%), and undefined TV (n = 585; 6.1%) were bridged. Balloon-expandable stent-grafts (B-EXP) were used in 40.9% and self-expandable (S-EXP) in 22.7% and undefined stents in 36.3%. The included studies had quality assessment scores ranging between 11/15 and 15/15, with high grade of accordance on reporting general results, but a low grade of accordance on reporting detailed data. Despite study heterogeneity, high-volume analysis confirmed a higher rate of complication in renal arteries than visceral arteries, 6% (95% CI 4–8) vs. 2% (95% CI 1–3), respectively. The rate of reinterventions was similar, 3% (95% CI 2–4) and 2% (95% CI 1–3). S-EXP versus B-EXP stent complication was 4% (95% CI 2–7) vs. 3% (95% CI 2–5), respectively. Conclusions: This systematic review underlines the low grade of accordance in reporting detailed data of bridging stents in F/B-EVAR. Renal TVs were more prone to complications, with an equivalent reintervention rate to visceral TVs. As to B-EVAR, the choice of B-EXP over S-EXP is still uncertain

    Hybrid rescue technique after failure of a standard multibranched stent graft

    Full text link
    A 78-year-old woman presented with type IIIC and IIID endoleaks after endovascular treatment for a thoracoabdominal aortic aneurysm. Mating between the ruptured segments of superior mesenteric artery stent graft was performed. After failed attempts at relining the right renal artery stent graft, a hybrid approach was used to connect the side branch to the target vessel: a stent graft was deployed into the side branch of the main graft and it was temporarily occluded with a balloon. After opening the sac, a stent graft was deployed into the right renal artery and the two stent grafts were connected with a running suture. Follow-up examination performed 1 month postoperatively by computed tomography imaging confirmed the effectiveness of this treatment

    Correlazione tra parametri TC ed analisi istologica nell’eterogenità di placca carotidea: studio pilota

    No full text
    Scopo di questo studio pilota è identificare parametri TC con mezzo di contrasto (TCMdC) in grado diidentificare placche carotidee (PC) ad alto grado di eterogenicità istologic

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    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
    corecore