1,721,044 research outputs found
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
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
Where We Mentalize: Main Cortical Areas Involved in Mentalization
No full textWhen discussing “mentalization,” we refer to a very special ability that only humans and few species of great apes possess: the ability to think about themselves and to represent in their mind their own mental state, attitudes, and beliefs and those of others. In this review, a summary of the main cortical areas involved in mentalization is presented. A thorough literature search using PubMed MEDLINE database was performed. The search terms “cognition,” “metacognition,” “mentalization,” “direct electrical stimulation,” “theory of mind,” and their synonyms were combined with “prefrontal cortex,” “temporo-parietal junction,” “parietal cortex,” “inferior frontal gyrus,” “cingulate gyrus,” and the names of other cortical areas to extract relevant published papers. Non-English publications were excluded. Data were extracted and analyzed in a qualitative manner. It is the authors' belief that knowledge of the neural substrate of metacognition is essential not only for the “neuroscientist” but also for the “practical neuroscientist” (i.e., the neurosurgeon), in order to better understand the pathophysiology of mentalizing dysfunctions in brain pathologies, especially those in which integrity of cortical areas or white matter connectivity is compromised. Furthermore, in the context of neuro-oncological surgery, understanding the anatomical structures involved in the theory of mind can help the neurosurgeon obtain a wider and safer resection. Though beyond of the scope of this paper, an important but unresolved issue concerns the long-range white matter connections that unify these cortical areas and that may be themselves involved in neural information processing
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
Double cystic brain metastasis in a patient with stable pancreatic intraductal papillary mucinous neoplasm
No full textBackground: Brain metastases in pancreatic cancer are a rare condition and are usually seen in case of pancreatic adenocarcinoma. Only few cases of brain metastasis in patients affected by Intraductal papillary mucinous neoplasm (IPMN) are actually reported. Case description: We report a patient diagnosed with double cystic brain lesions that the histological examination reveal to be consistent, with pancreatic metastasis. Our patient had an history shown of stable pancreatic IPMN which has never made the oncologist suspicious about neoplastic progression or degeneration into pancreatic carcinoma. Considering the rarity of these metastasis we did a literature review on the topic Conclusions: Despite rare, pancreatic origin of a cystic brain metastasis should considered in differential diagnosis in both patient with IPMN or patient with unknown primitive tumor
A systematic review on the role of the endoscope in the surgical management of cerebellopontine angle tumors: is it time to draw the conclusion?
Full text linkObjective: The use of the endoscope has brought major changes in skull base surgery in the last decades. In the cerebellopontine angle (CPA), it has shown few advantages over microscopic surgery alone, evolving towards a full-endoscopic surgery for neurovascular conflicts and tumors. This review aims to systematically analyze the literature about the use of the endoscope in the cerebellopontine angle tumors. Methods: Pubmed/Medline and Embase databases were investigated applying PRISMA guidelines without time restrictions to find all adult patients affected by an extra-axial cerebellopontine angle tumor (vestibular schwannoma, meningioma, epidermoid tumor, or other extra-axial lesions) treated using only the endoscope (full-endoscopic, FE or endoscopic-controlled, EC) or with endoscopic assistance (EA). Results: After article selection, a total of 2489 patients have been treated for a CPA lesion using the endoscope: 2054 vestibular schwannomas (VS), 368 epidermoid tumors (ET), 41 meningiomas and 26 among other pathologies. The retrosigmoid approach was the most frequently employed surgical corridor, irrespective of lesion type, for both full-endoscopic and endoscopic-assisted procedures. Although a great heterogeneity should be highlighted among the selected series of VS (1539), a weighted average of 92.5% of gross total resection (GTR) was obtained and 90% out of 1332 showed a good facial nerve outcome when comparable. Advantages in term of recognition of residuals have been described for the CPA meningiomas and multicompartmental epidermoid tumors with origin from CPA cistern, without increasing the risk of complications. Conclusions: Despite different accepted advantages, the number of tumors in which the endoscope has been included among the surgical armamentarium is still limited compared to the number of the full-microscopic resections. After almost 30 years since its value was recognized, the number of prospective and case-control studies is still scarce to affirm a real benefit leading to its routinary use
Double concentric craniotomy: Safe and effective technique to achieve an en bloc resection of tumor involving both skull and duraa
Full text linkAbstractIntroductionMany tumors can involve the skull. Meningiomas are one of the most common intracranial neoplasms and invasion of the bone was described in 49% of cases. Other neoplastic lesions that can arise in bone, or involve it, are metastases, hemangiomas, aggressive cutis carcinomas and sarcomas. Radical excision is the golden standard of treatment but elevating a bone flap when the tumor involves both the skull and the dura could represent a technical challenge.Presentation of caseWe report the technical details of our approach to remove a meningioma involving both skull and dura in a man aged 45. Patient underwent gross total excision and cranioplasty with PEEK custom made prothesis (Synthes™).DiscussionWe describe a double concentric craniotomy (DCC) technique where the tumor involving the bone is before left in situ, exposing normal dura, to perform afterwards en-bloc excision with minimal traction of brain surface.ConclusionDCC is a safe and effective technique to remove tumor involving both skull and dural structures under direct vision
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
- …
