1,721,093 research outputs found
Endoscopic-assisted removal of ventricular catheter in high-risk patients
No full textIntroduction. Ventriculoperitoneal shunt carries a non-negligible failure rate often requiring multiple surgical procedures during patient-s lifetime. The most common cause is obstruction of the ventricular catheter that can be embedded in adhesions with choroid plexus, ependymal tissue, and fibrous material. In such cases, or when an intraventricular tumor is present, particular attention must be paid when removal of the ventricular catheter is required. The potential adhesions with the tip of the ventricular catheter results in an increased risk of life-threatening hemorrhage. Materials and methods. We present the case of a ventriculoperitoneal shunt proximal revision in a von Hippel-Lindau affected patient. The neuroendoscopic exploration to restore the patency of the ventricular system made it possible to notice a fibrous adhesion between the tip of the catheter and a pituitary hemangioblastoma abutting into the third ventricle. Discussion. Pituitary stalk hemangioblastoma is an infrequent localization, although it represents the most common supratentorial site of hemangioblastoma in patients affected by von Hippel-Lindau syndrome. In this and in similar cases, endoscopic-assisted shunt revision allows visualizing the tip of the ventricular catheter and eventual adhesions that can be coagulated and cut by simple maneuvers, without any morbidity for patients. Conclusion. In a ventriculoperitoneal shunt revision with the concomitant presence of an intraventricular tumor or lesion at risk of bleeding, the surgical procedure should be performed under neuroendoscopic observation to reduce the risk of intraventricular hemorrhage
Hemangioblastoma of the Filum Terminale Resected with the Aid of Intraoperative Indocyanine Green Angiography in a Patient Affected by Von Hippel Lindau Disease
No full textSymptomatic Anterior Cerebral Artery Vasospasm after Brainstem Hemangioblastoma Resection: A Case Report
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Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
Mechanisms of motor recovery in chronic and subacute stroke patients following a robot-aided training
No full textThe aim of this article is to propose a methodology for analyzing different recovery mechanisms in subacute and chronic patients through evaluation of biomechanical parameters. Twenty-five post-stroke subjects, eight subacute and seventeen chronic, participated in the study. A 2-DoF robotic system was used for upper limb training. Two clinical scales were used for assessment. Forces and velocities at the robot's end-effector during the execution of upper limb planar reaching movements were measured. Clinical outcome measures show a significant decrease in motor impairment after the treatment both in chronic and subacute patients (MSS-SE, p<0.001; FM, p<0.05). Movement velocity increases after the robot-aided treatment in both groups. Mean values of forces exerted by subacute patients are lower than those observed in chronic patients, both at the beginning and at the end of robotic treatment, as in the latter the pathological pattern is already structured. Our results demonstrate that the monitoring of the forces exerted on the end-effector during robot-aided treatment can identify the specific motor recovery mechanisms at different stages. If the pathological pattern is not yet structured, rehabilitative interventions should be addressed toward the use of motor re-learning procedures; on the other hand, if the force analysis shows a strong pathological pattern, mechanisms of compensation should be encouraged. © 2013 IEEE
Epidemiological study on knowledge, attitudes and behaviour of health care workers with respect to HIV infection
No full textDispelling the Myths Behind First-author Citation Counts
No full textWe 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
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