1,721,146 research outputs found
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
Letter to the Editor: EUS-FNA for Lymph Nodes Staging in Cholangiocarcinoma: Should It Become Standard of Care?
No abstract availabl
Anatomical liver resection of segment 4a en bloc with the caudate lobe
Anatomical segmentectomy is the complete resection of an area supplied by a segmental portal branch. Among segmentectomies, isolated segmentectomy 4 is a technically demanding procedure because there are two transection planes: on the left side along the umbilical fissure and, on the right side, along the middle hepatic vein. Although there are several reports on anatomic segmentectomies, only few regard the anatomic segmentectomy 4a. We report here the case of a 60-year-old man who underwent anatomical segmentectomy 4a en bloc with the caudate lobe to resect a colorectal liver metastasis located in segment 4a and involving the paracaval portion of the caudate lobe. This type of procedure was planned in order to maximize the postoperative functional hepatic reserve, thereby reducing the risk of postoperative liver failure and ultimately allowing the possibility for future repeat hepatectomy in case of recurrence. J. Surg. Oncol. 2016;113:665-667. © 2016 Wiley Periodicals, Inc
Primary Hepatic Angiosarcoma
Primary hepatic angiosarcoma is a rare entity, representing only 4%
of all the angiosarcomas of different origins1 and less than 1% of all
hepatic malignancies.2
Accurate diagnosis of this tumour is difficult, especially if the
patient has no history of exposure to specific carcinogens including
thorotrast, arsenicals and vinyl chloride monomer.3
Angiosarcoma, a subtype of soft tissue sarcoma, is an aggressive
malignant disease deriving from endothelium, lymphatics or blood
vessels. Some of the more common hepatic sarcomas are angiosarcoma,
embryonal sarcoma, leiomyosarcoma, epithelioid hemangioendothelioma,
fibrosarcoma and malignant fibrous histiocytoma.2
The survival of hepatic angiosarcoma is very poor, which is attributable
to its rapid progress, high recurrence rate and resistant to
traditional chemotherapy and radiotherapy.4 The survival of patients
with liver angiosarcoma is very poor with median survival of 6
months without treatment; after treatment, only 3% of patients were
reported to live longer than 2 year
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
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