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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Intrasellärt tryck hos patienter med hypofystumör : koppling till syn- och endokrina funktioner, komplikationer och prognos efter kirurgi
No full textBackground: The pathophysiological mechanisms behind the development, symptoms, operative results, and complications of pituitary tumors are not fully understood. A much-neglected factor is the pressure profile in the sellaturcica (intrasellar pressure) which harbors the pituitary gland. Hypothesis and Aim: The aim of this thesis is to explore the pathophysiological mechanisms involved in pituitary tumordisease, with special focus on the role of intrasellar pressure (ISP). The underlying hypothesis is that ISP is associated with symptoms and prognosis after pituitary tumor surgery. Method: The thesis includes four studies of different aspects of pituitary tumor disease, and their associations with ISP. These were single-center, retrospective studies based on the same well-characterized and consecutively collected population, albeit with some differences in exclusion criteria. All subjects were operated on for a pituitary tumor at the Neurosurgical Department, Umeå University Hospital, in 2009–2015, and had their ISP measured intraoperatively. Data on patient and tumor characteristics, symptoms, complications, and recovery were collected from medical files from the preoperative investigation and postoperative follow-up (3 months). Results: In Paper I, we analyzed the impact of tumor anatomy and growth pattern on ISP. There was a positive correlation between ISP and tumor volume. Coronal tumor diameter (i.e., tumor width) showed stronger correlation with increased ISP than tumor growth in the other planes. Invasive tumors in the parasellar direction (Knosp III–IV) showed higher mean ISP than non-invasively growing tumors. In Paper II, we evaluated hormonal disturbances pre- and postoperatively in relation to ISP. ISP was positively associated with the risk of preoperative hyperprolactinemia (in non-prolactinoma tumors) and the risk of preoperative thyroidstimulating hormone insufficiency. No association between ISP and the risk of preoperative adrenocorticotropic hormone insufficiency was found. No correlations were found between ISP and the risk of postoperative hormonal insufficiency at 3months after surgery. In Paper III, the relations of ISP and tumor and patient characteristics to pre- and postoperative visual acuity, visual field,and cranial nerve III, IV, and VI deficits were studied. High ISP and large tumor volume were associated with increased risk of postoperative visual acuity deficits after pituitary surgery. High age was a risk factor for postoperative visual field deficits and decreased the chance of visual acuity improvement after surgery. Large tumor volume, suprasellar tumor extension, and female sex were risk factors for preoperative visual acuity and visual field deficits. In Paper IV, the risk factors for intra- and postoperative complications in endoscopic transsphenoidal pituitary surgery(ETS) were explored. There was no substantial correlation between ISP and complications. Large tumor volume was a riskfactor for intraoperative complications, and low age a risk factor for postoperative cerebrospinal fluid leakage. Conclusions: ISP is elevated above expected normal levels in patients with a pituitary tumor. ISP is positively associated with tumor volume. Tumor growth in a parasellar direction gives rise to higher ISP than growth in other directions. High ISP is associated with a higher risk of preoperative hyperprolactinemia and hypopituitarism in the thyroid axis. These results harmonize with the “stalk compression theory.” ISP seems not to affect hormonal recovery at 3 months. Anassociation between ISP and postoperative visual acuity impairment was seen, however, ISP was not identified as an important risk factor for visual symptoms or outcome. ISP does not seem to be a significant risk factor for intra- orpostoperative complications in ETS. ISP is heterogeneously associated with tumor anatomy, symptoms, pathophysiology and surgical outcomes in pituitary tumor disease. This thesis provides no evidence supporting routine ISP measurement during pituitary surgery, unless ISP is the primary variable of interest in research.
Variations on the Author
Get PDF“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
Get PDFWe 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
Intrasellärt tryck hos patienter med hypofystumör : koppling till syn- och endokrina funktioner, komplikationer och prognos efter kirurgi
No full textBackground: The pathophysiological mechanisms behind the development, symptoms, operative results, and complications of pituitary tumors are not fully understood. A much-neglected factor is the pressure profile in the sellaturcica (intrasellar pressure) which harbors the pituitary gland. Hypothesis and Aim: The aim of this thesis is to explore the pathophysiological mechanisms involved in pituitary tumordisease, with special focus on the role of intrasellar pressure (ISP). The underlying hypothesis is that ISP is associated with symptoms and prognosis after pituitary tumor surgery. Method: The thesis includes four studies of different aspects of pituitary tumor disease, and their associations with ISP. These were single-center, retrospective studies based on the same well-characterized and consecutively collected population, albeit with some differences in exclusion criteria. All subjects were operated on for a pituitary tumor at the Neurosurgical Department, Umeå University Hospital, in 2009–2015, and had their ISP measured intraoperatively. Data on patient and tumor characteristics, symptoms, complications, and recovery were collected from medical files from the preoperative investigation and postoperative follow-up (3 months). Results: In Paper I, we analyzed the impact of tumor anatomy and growth pattern on ISP. There was a positive correlation between ISP and tumor volume. Coronal tumor diameter (i.e., tumor width) showed stronger correlation with increased ISP than tumor growth in the other planes. Invasive tumors in the parasellar direction (Knosp III–IV) showed higher mean ISP than non-invasively growing tumors. In Paper II, we evaluated hormonal disturbances pre- and postoperatively in relation to ISP. ISP was positively associated with the risk of preoperative hyperprolactinemia (in non-prolactinoma tumors) and the risk of preoperative thyroidstimulating hormone insufficiency. No association between ISP and the risk of preoperative adrenocorticotropic hormone insufficiency was found. No correlations were found between ISP and the risk of postoperative hormonal insufficiency at 3months after surgery. In Paper III, the relations of ISP and tumor and patient characteristics to pre- and postoperative visual acuity, visual field,and cranial nerve III, IV, and VI deficits were studied. High ISP and large tumor volume were associated with increased risk of postoperative visual acuity deficits after pituitary surgery. High age was a risk factor for postoperative visual field deficits and decreased the chance of visual acuity improvement after surgery. Large tumor volume, suprasellar tumor extension, and female sex were risk factors for preoperative visual acuity and visual field deficits. In Paper IV, the risk factors for intra- and postoperative complications in endoscopic transsphenoidal pituitary surgery(ETS) were explored. There was no substantial correlation between ISP and complications. Large tumor volume was a riskfactor for intraoperative complications, and low age a risk factor for postoperative cerebrospinal fluid leakage. Conclusions: ISP is elevated above expected normal levels in patients with a pituitary tumor. ISP is positively associated with tumor volume. Tumor growth in a parasellar direction gives rise to higher ISP than growth in other directions. High ISP is associated with a higher risk of preoperative hyperprolactinemia and hypopituitarism in the thyroid axis. These results harmonize with the “stalk compression theory.” ISP seems not to affect hormonal recovery at 3 months. Anassociation between ISP and postoperative visual acuity impairment was seen, however, ISP was not identified as an important risk factor for visual symptoms or outcome. ISP does not seem to be a significant risk factor for intra- orpostoperative complications in ETS. ISP is heterogeneously associated with tumor anatomy, symptoms, pathophysiology and surgical outcomes in pituitary tumor disease. This thesis provides no evidence supporting routine ISP measurement during pituitary surgery, unless ISP is the primary variable of interest in research.
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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