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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Prognostic factors in surgical resection of sacral chordoma

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    Background and objectives: The best treatment of sacral chordoma is surgical resection, nowadays associated with optimized radiation therapy. We analysed 1) the oncologic outcome in a large series; 2) the effect of previous intralesional surgery, resection level, tumor volume and margins on survivorship to local recurrence (LR) and 3) the complication rate. Methods: We reviewed 71 patients with sacral chordomas. Forty-eight resections were proximal to S3. Mean tumor volume was 535 cm3. Eleven received previous intralesional surgery elsewhere. Margins were wide in 44 resections, wide-contaminated in 11, marginal in 9 and intralesional in 7. Results: Overall survival was 92%, 65% and 44% at 5, 10 and 15 years. At a mean of 9.5 years 37 were NED (54.4%), 23 died with disease (33.8%) and 8 were alive with disease (11.7%). Relapses included 15 LRs, 6 distant metastases, 17 both. LR rate was significantly higher in patients with previous surgery (p = 0.0217), with inadequate margins (p = 0.0339) and large tumors(p< 0.01), whereas resection level was not significant. Multivariate analysis confirmed the role of tumor volume. Complication rate was high (80.9%) with an infection rate of 41.2%. Conclusions: The most prominent adverse factor for LR was previous intralesional surgery. LR rate was related with inadequate margins and tumor volume. (c) 2015 Wiley Periodicals, Inc

    Treatment of Osteoid Osteomas of the Foot: A Review of 100 Cases

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    Objectives: Osteoid osteoma (OO) is a small, benign, osteogenic bone tumor, with less than 11% of cases located in the feet. We review our experience in OO of the foot bones in order to characterize its prevalence, treatment, and recurrence rate at long term follow up. Methods: The medical records of 100 cases of osteoid osteoma of the foot treated between 1975 and 2009 were reviewed retrospectively. There were 73 male and 27 female patients, with a mean age of 23.4 years (7-61 years). The lesions were located in the talus (n=59), calcaneus (n=14), metatarsal bones (n=9), cuneiform bones (n=5), phalanges (n=4), cuboid (n=4), navicular (n=2) and tarsal bones, not otherwise specified (n=3). None of the patients had received prior percutaneous or surgical treatment for the tumor. Twelve tumors were intra-articular and 88 extra-articular. All patients were taking routine analgesics including anti-inflammatory medications. Results: Treatment consisted of radiofrequency ablation (RFA) in 43 patients, excisional CT-guided trocar biopsy, or percutaneous drill resection (PDR) in 21 patients, intra-lesional curettage in 43 patients, and wide resection alone as well as wide resection with total ankle arthroplasty in one patient each. Adequate follow-up was available for all patients. One patient treated with RFA reported recurrent pain after 2 months and was successfully treated with a second RFA. The overall recurrence rate was 1%; however, it was 2.3% in those patients treated with RFA. No adverse events related to treatment or to the anatomical location were recorded. Conclusion: RFA is a safe and effective alternative to surgical resection of osteoid osteomas of the foot. Caution should be taken when performing this procedure on lesions less than 1 cm from neurovascular structures or in superficial locations, due to risk for soft tissue injury from thermal necrosis

    Treatment of pathologic fractures of the proximal femur

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    Abstract Background Metastatic lesions to the proximal femur occur frequently and require special consideration due to the high risk of pathologic fractures. Type of surgery might influence patient survival considering the growing concept of oligometastases. In fact, the use of modular tumor megaprosthesis is increasing in the last decades compared to intramedullary nailing. Aim of this study was to evaluate oncological and functional results of treatment in patients with pathologic or impending fracture of the proximal femur, with patient survival being the primary, complications the secondary, and functional results the tertiary endpoint. Methods Between 2016 and 2017, 40 patients with pathologic fracture (29 cases) or impending fracture according to the Mirels score (11 cases) of the proximal femur, were treated in our Institute and prospectively collected. There were 29 females (72.5%) and 11 males (27.5%), with a mean age at diagnosis of the metastasis of 63.6 years (range 35 to 92 years). Patients were treated due to bone metastases (commonly develop from breast cancer) or hematologic malignancies. Considering number of lesions, 17 patients had less than three bone metastases. Surgical procedures included intramedullary nailing (7 patients), conventional endoprosthesis (4 patients) and modular endoprosthetic replacement (29 patients). Adjuvant treatments included chemotherapy (13 cases), radiation therapy (8 cases) or both (15 cases), and selective arterial embolization (6 pre-op). Oncological results were evaluated considering the survival of patients. Functional results were assessed as pain intensity in VAS score and MSTS score. Results The mean follow-up of patients was 10.2 months (range 6–26.3 years). At the latest evaluation, 23 patients were alive with disease, 3 patients were alive without evidence of disease and 14 patients were dead with disease. There was a significant better survival in patients treated with PFR compared to IMN and EPR groups (p = 0.0080). No differences in term of survival were found comparing impending vs actual pathological fracture and oligo vs multiple metastases. After surgery, all patients experienced improvement in quality of life resulting from reduction in pain. Mean MSTS score was 22.4. The overall complications rate was 22.5%. The most frequent complication was dislocation followed by wound dehiscence and deep infections. Conclusion Modular tumour prosthesis for proximal femur replacement provides good functional outcome, relative low incidence of complications and higher life quality in the medium term. Oncologic results were influenced by type of surgery, biased by the correct indications for resection and nailing. Preoperative general health condition, life expectancy and ambulatory capacity may influence treatment strategy. With the numbers available, the patients with actual pathologic or impending fracture of the proximal femur treated with resection had a significantly higher survival, especially those with metastases from renal carcinoma or multiple myeloma

    Variations on the Author

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    “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

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    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

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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
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