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    'Internal bracing' surgery in the management of solid tumor metastases of the thoracic and lumbar spine

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    In patients with thoracolumbar spine metastasis, surgery is aimed at patient healing only when patient has a good prognosis with long life expectancy. In patients with short life expectancy a less aggressive surgical approach of posterior decompression and stabilization could improve patient care and allow for neurological recovery. Thirty-two consecutive patients affected by symptomatic thoracolumbar spine metastases with short life expectancy and good Karnofsky index (50-70) were subjected to surgery and reviewed retrospectively. After tumor embolization, surgery consisted of posterior decompression and stabilization with laminar hooks in the dorsal spine, and laminar hooks or lumbar pedicle screws. Patient's Karnofsky Index, average survival, Frankel neurological status, and pain were recorded before and after surgery, together with surgery related complications. Primary tumors were breast carcinoma (nine patients), renal cell carcinoma (three), lung carcinoma (four), GI tract carcinoma (six), prostate carcinoma (two), carcinoma of the uterus (two), melanoma (three), and malignant tumors at other different sites (three). Average survival after surgery was 23 months, with highest survival rates in renal cancer and breast carcinoma patients, and poorest survival rates in lung and dedifferentiated carcinoma. Karnofsky index improved from average 61 to 72% posto-peratively. After surgery patients experienced significant overall improvement of Frankel score and decrease of referred pain. Hospitalization stay was on average 10 days. Results showed that operative treatment of symptomatic spinal metastases in patients with poor prognosis and good general health status improves or preserves neurological function, allows for adjuvant treatments to be performed and has a role in improving general health status in most patients

    Clinical significance of different effects of static and pulsed electromagnetic fields on human osteoclast cultures

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    Electromagnetic fields are known to affect the bone metabolism by modifying some relevant physiologic cell parameters of cells, even though the underlying mechanisms are still unclear. The aim of our study was to evaluate the effect of both static magnetic fields (SMFs) of the same intensity of the one generated by spinal metal devices and pulsed electromagnetic fields (PEMFs) of the same intensity used for the management of nonunion on human osteoclasts cell culture. Primary osteoclast cells were isolated from primary human osteoclast precursors and were exposed to SMFs and to PEMFs. Morphology and tartrate-resistant acid phosphatase (TRAP) activity were evaluated in the osteoclast cultures after 7, 10, and 14 days of exposure. The SMF-exposed cells show a more differentiated phenotype and a significantly higher TRAP activity after 7 and 10 days of treatment with respect to a sham control. PEMF-exposed cells have a less-differentiated phenotype after 7 days of exposure compared with the relative sham control, while the TRAP activity shows no statistically significant differences between exposed and control cells at any observation time. Our results indicate that SMFs of the same intensity of the one generated around spinal devices can affect osteoclast differentiation and activity. Aseptic loosening around titanium implants might be due in part to an increased osteoclast activity and differentiation. PEMFs of the same intensity than the one used for the management of nonunions can affect osteoclasts phenotype after 7 days of exposure, while osteoclasts TRAP activity is not affected by this kind of electromagnetic fields

    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

    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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