1,720,988 research outputs found
Late open conversion after endovascular abdominal aortic aneurysm repair: experience of three-high volume centers
BACKGROUND: Accumulated endovascular aneurysm repair (EVAR) procedures will increase number of patients requiring conversion to open repair of abdominal aortic aneurysms (AAA). In most cases, patients undergo late open surgical conversion (LOSC), many months, or years, after initial EVAR. The aim of this study is to analyze results of LOSC after EVAR in elective and urgent setting, including presenting features, surgical techniques, as well as to review the clinical outcomes and their predictors. METHODS: Retrospective review of all consecutive patients undergoing LOSC after EVAR was performed at three distinct, high volume, vascular centers. Patients that required primary conversion within 30 days after EVAR have not been included in this study. Between January 1st 2010 and January 1st 2017 total of 31 consecutive patients were treated. LOSC were performed either in elective or in urgent setting, thus dividing patients in two groups. Primary outcome was 30-day mortality and secondary postoperative complications RESULTS: LOSC rate after EVAR was 4.51%. Most common indication for LOSC was type I endoleak (N.=20, 64.51%). All patients that presented with ruptured AAA had some form of endoleak (type I endoleak was present in five from six cases). Most common site for aortic crossclamping was infrarenal (51.61%). Stent-graft was removed completely in 18 patients (58.06%) and partially in 13 (41.93%). 30-day mortality rate was 16.12% (5 patients) and most common cause of death was myocardial infarction (60%). Following univariate factors were isolated as predictors for 30-day mortality: preoperative coronary artery disease, chronic obstructive pulmonary disease, urgent LOSC, prolonged time until LOSC. ruptured AAA. supraceliac clamp. higher number of red blood cell transfusion, postoperative myocardial infarction, and prolonged intubation (more than 48 hours). CONCLUSIONS: LOSC seems to be safe and effective procedure when preformed in elective manner. On the other side, urgent LOSC after EVAR is associated with very high postoperative mortality and morbidity. Endoleak remains the main indication for open conversion. Further studies are necessary to standardize timing and treatment options for failing EVAR
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
Acute kidney injury in patients undergoing endovascular or open repair of juxtarenal or pararenal aortic aneurysms
Background: The aim of this cohort study was to report the proportion of patients who develop periprocedural acute kidney injury (AKI) after endovascular repair (ER) and open surgery (OS) in patients with juxta/pararenal abdominal aortic aneurysm and to assess potential risk factors for AKI. The study also aimed to report the short- and long-term outcomes of patients with and without AKI. Methods: This was a multicenter cohort study of five European academic high-volume centers (>50 OS or 50 ER infrarenal AAA repairs, plus >15 complex AAA repairs per year). All consecutively treated patients were extracted from a prospective vascular surgical registry and the data were scrutinized retrospectively. The primary end point for this study was the development of AKI. AKI was diagnosed when there is a two-fold increase of serum creatinine or decrease of glomerular filtration rate of >50% within 1 week of AAA repair. Secondary end points included long-term mortality and end-stage renal disease (ESRD). Results: AKI occurred in 16.6% of patients in the ER group vs 30.3% in the OS group (P <.001). The 30-day mortality rate was higher among patients with AKI in both ER (15.4% vs 3.1%; P =.006) and OS (13.2% vs 5.3%; P =.001) groups. Age, chronic kidney disease, presence of significant thrombus burden in the pararenal region, >1000 mL blood loss in ER group were associated with development of AKI. Age, diabetes mellitus, chronic kidney disease, presence of significant thrombus burden in the pararenal region, and a proximal clamping time of >30 minutes in the OS group were associated with the development of AKI, whereas renal perfusion during clamping was the protective factor against AKI development. After a median follow-up of 91 months, AKI was associated with higher mortality rates in both the ER group (58.9% vs 29.7%; P <.001) and the OS group (61.5% vs 27.3%; P <.001). After the same follow-up period, AKI was associated with a higher incidence of ESRD in both the ER group (12.8% vs 3.6%; P =.009) and the OS group (9.9% vs 2.9%; P <.001). Conclusions: The current study identified important pre and postoperative factors associated with AKI after juxta/pararenal abdominal aortic aneurysm repair. Patients with postoperative AKI had significantly higher short- and long term mortality and higher incidence of ESRD than patients without AKI
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We 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.
Author-wise bibliometric analysis based on entropy.</p
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