1,720,970 research outputs found
Chordomas and Chondrosarcomas Involving the Cavernous Sinus
No full textChordomas and chondrosarcomas are rare, infiltrative, and slow-growing tumors that arise in the skull base from clival and petroclival regions. Despite radiological similarities, the histological origin and prognosis are different. Gross total resection, preserving function and quality of life, followed by radiotherapy represents the gold standard for chordomas and high-grade chondrosarcomas. Considering the infiltrative nature and the involvement of cranial nerves and vessels, they still represent a surgical challenge. The introduction of endoscopic techniques has completely changed the surgical strategies, particularly in case of cavernous sinus invasion. Endoscopic techniques allow direct faster without crossing neurovascular structures, resulting in better functional and oncological outcome. Most often, radical primary surgery is the only chance of cure, and with that, it is of tremendous importance to refer those patients to specialized skull base centers with expertise in both microscopic and endoscopic techniques, supported by a multidisciplinary team
Endoscopic Endonasal Approach to Cavernous Sinus and Middle Cranial Fossa
No full textCavernous sinus surgery has evolved in the last decades moving toward less invasive approaches to reduce postoperative morbidities. Endoscopic endonasal techniques have been a revolution in skull base surgery providing a natural and direct line of sight to deep-seated skull base lesions such as the cavernous sinus, complementing the standard transcranial approaches. In this chapter, endoscopic anatomy, patient selection and contraindications, and surgical technique among clinical cases are provided
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
Chordomas and Chondrosarcomas of the Posterior Fossa
No full textSkull base chordomas and chondrosarcomas are rare bone neoplasms that develop around the clivus and the petroclival region. Although they are quite similar in terms of clinical and radiological features, chordomas and chondrosarcomas differ with regard to their origin and prognosis. The optimal treatment for skull base chordomas and high-grade chondrosarcomas includes radical surgical resection followed by high-dose radiotherapy. Because of chordomas and chondrosarcomas rarity and complex location, the surgical management of these lesions should be carried out exclusively by expert skull base teams. Providing a unique trajectory to the clivus, the endoscopic endonasal approach has considerably changed the surgical management of posterior fossa chordomas and chondrosarcomas in the last two decades. However, limitations remain, and transcranial approaches remain the best adjunct for complex lesions extending beyond the limits of what can be safely achieved with endoscopic techniques. Endoscopically assisted transcranial approaches have also made possible to widen the exposure of classic transcranial approach and to reduce the aggressiveness of the approach. For chordomas, radical resection, including infiltrated bone, remains the goal, as it is the most important prognostic factor. Skull base chondrosarcomas carry a more favorable outcome than chordomas with a better long-term control. Conversely, despite aggressive treatment, chordomas have a high rate of recurrence. The development of medical targeted therapies is strongly needed to improve the outcome of patients with advanced disease
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
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
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