1,721,013 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Follicular thyroid carcinoma with metastases to the pituitary causing pituitary insufficiency.
BACKGROUND: Pituitary metastases are found in about 1% of all pituitary resections. They often derive from breast, lung, and gastroenteric tract adenocarcinomas, very rarely from thyroid carcinoma. Presenting symptoms of thyroid carcinoma metastatic to the pituitary gland are usually chiasmatic with central neurological impairment due to space-occupying expansion in the parasellar region. Hypopituitarism is more often associated with papillary and medullary rather than follicular thyroid carcinoma (FTC). Here we describe a patient with pituitary metastasis from FTC who had hypopituitarism with thyrotropin (TSH) deficiency.
SUMMARY: A 61-year-old woman, who presented with visual deficits and pain to the right orbit, was found on magnetic resonance imaging to have a large mass involving the pituitary gland. She was found to have pituitary insufficiency based on corticotropin-releasing hormone and TSH-releasing hormone testing. Transnasopharyngeal biopsy of the mass revealed metastases from FTC. After total thyroidectomy, which confirmed widely invasive FTC, the patient underwent external beam radiation therapy of the metastases for progressive neurological symptoms and an increase in orbit pain. Since endogenous TSH production was insufficient, we used recombinant human TSH (rhTSH) as preparation for a series of radioiodine treatments. rhTSH administration, followed by 7.4 GBq of (131)I, was repeated seven times over a 10-year period. This was associated with a marked decrease in serum thyroglobulin levels accompanied by substantial clinical improvement, but after 7 years disease progression occurred.
CONCLUSIONS: Seven patients with pituitary metastases from FTC have been reported. In all cases, some neurological signs and symptoms related to mass effect were reported, but no pituitary insufficiency was described. This may be the first case of FTC with metastases to the pituitary causing hypopituitarism. It seems likely that management of such cases could be limited to biopsy to confirm thyroid carcinoma, rather than more extensive surgery, and that this could be followed by multiple treatments with rhTSH followed by (131)I
Analisi radiomica delle modificazioni dopo radioterapia neoadiuvante in pazienti con adenocarcinoma del pancreas
No abstract availabl
Out-patient high-dose-rate endobronchial brachytherapy for palliation of lung cancer: An observational study
BACKGROUND AND AIM:
Out-patient high-dose-rate endobronchial brachytherapy (HDREB) is a possible option in the palliation of symptoms in patients with advanced lung cancer, but literature data is limited and the technique is still under development in Italy. Our aim was to evaluate safety and effectiveness of out-patient HDREB for palliation of malignant endobronchial tumours in the context of a multidisciplinary approach.
METHODS:
Out-patient HDREB sessions were scheduled at weekly intervals (500-1000 cGy per session) with prior Diodi-laser resection in some cases. Response was assessed bronchoscopically, clinically and functionally at the end of treatment and one month after the last HDREB session. Inclusion criteria was: histological evidence of malignant tumour not susceptible to surgical treatment for extension or co-morbidity.
RESULTS:
150 outpatient HDREB sessions were carried out on consecutive 35 patients (mean age 69 yrs, M/F 29/6) with symptoms due to central airway obstruction. A shortterm endoscopic response was observed in 15/28 patients. After delivering 2000 cGy dyspnoea decreased significantly. After one month cough decreased and haemoptysis disappeared. Palliation was obtained in all patients except one during. Lung function tests did not significantly improve after HDREB. No fatal complication occurred. A temporary radiation bronchitis was observed in six patients.
CONCLUSIONS:
This non-comparative, prospective observational study showed a palliative response of HDREB in most of patients with advanced endoluminal lung cancer. The safety of the procedure was good and the rate of non-fatal serious complications was very low
Dispelling the Myths Behind First-author Citation Counts
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
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