1,720,973 research outputs found
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
Giant Thoracic Meningocele: A Multidisciplinary Surgical Approach with Innovative Exclusion Technique
No full textThoracic meningocele is a rare medical condition that is usually linked to neurofibromatosis type I.1 Respiratory and neurologic symptoms characterize it.2 Although there have been some improvements in surgical techniques, the condition has a high recurrence rate, with most cases recurring within a year of surgery.3 A 56-year-old woman was observed due to respiratory and pyramidal signs. A chest computed tomography scan and magnetic resonance imaging revealed a thoracic meningocele, occupying the lower sectors of the right hemithorax, communicating with the cerebrospinal fluid space at the T10-T11 level. Multidisciplinary surgery was performed. After selectively intubating both bronchi, the patient was placed in prone position and a posterior median thoracic spine approach was performed. After T10-T11 laminectomy, 3 dural longitudinal incisions were performed. The first incision was placed in the middle to deflate the collection, the second was made on the right side to obtain a complete view of the meningocele, and the third was made on the right lateral side to exclude the meningocele. The lateral dura at the last incision was sutured to the dura propria lining the vertebral body of T11 and T10. The paramedian and median incisions were closed, with Tachosil placed above and below the sutures. Subsequently, the patient was placed in a supine position, the right lung was deflated, and a triportal thoracoscopic approach was performed to dissect and remove the lesion.4 The breach was closed using Tachosil (Baxter Healthcare Corp, Deerfield, Illinois, USA) and fibrin glue. An early 1-month computed tomography and magnetic resonance imaging confirmed the surgery was successful
Giant "Dumbbell" Thoracic Schwannoma: Radical Excision of Rare Lesion in One Surgical Time by Combined Neurosurgical and Thoracoscopic Approach
No full textDumbbell-shaped schwannomas are slow-growing tumors that are typically benign lesions. They account for 6%–14% of spinal neoplasms, with 30% having intradural and extradural components.1 A schwannoma is considered “giant” if it extends beyond the spine by >2.5 cm and involves more than 2 vertebral levels.2 The Eden classification categorizes these tumors into 4 types on the basis of the primary component.3 Surgery is recommended for individuals experiencing prolonged nerve damage and persistent neurogenic pain that cannot be managed.2 There are 3 surgical options for managing thoracic dumbbell schwannomas4: the single-stage posterior-only approach,5 the single-stage anterior-only approach,6 and the single-stage combined posteroanterior neurosurgical and video-assisted thoracoscopic approach. The latter option allows for the most comprehensive lesion control including vascular and nerve structures and optimal hemostasis control. It also avoids spinal instrumentation and provides certainty for complete tumor removal.7 Video 1 shows a surgical procedure performed on a 58-year-old woman to remove a thoracic dumbbell neurinoma. The patient consented to the procedure and publication of her image. A simultaneous thoracoscopic and neurosurgical approach was performed. The surgical team successfully removed the schwannoma, and the patient's recovery was smooth, with no neurologic issues or pain. This case highlights the benefits of using a single-stage combined approach for treating Eden II and Eden III giant dumbbell thoracic schwannomas
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
“Vascular inflammation and cardiovascular disease: review about the role of PET imaging”
No full textInflammation characterizes all stages of atherothrombosis and provides a critical pathophysiological link between plaque formation and its acute rupture, leading to coronary occlusion and heart attack. In the last 20 years the possibility of quantifying the degree of inflammation of atherosclerotic plaques and, therefore, also of vascular inflammation aroused much interest. (18)Fluoro-deoxy-glucose photon-emissions-tomography ((18)F-FDG-PET) is widely used in oncology for staging and searching metastases; in cardiology, the absorption of (18)F-FDG into the arterial wall was observed for the first time incidentally in the aorta of patients undergoing PET imaging for cancer staging. PET/CT imaging with (18)F-FDG and (18)F-sodium fluoride ((18)F-NaF) has been shown to assess atherosclerotic disease in its molecular phase, when the process may still be reversible. This approach has several limitations in the clinical practice, due to lack of prospective data to justify their use routinely, but it’s desirable to develop further scientific evidence to confirm this technique to detect high-risk patients for cardiovascular events
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