1,720,996 research outputs found

    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

    Pulmonary alveolar microlithiasis: review of the 1022 cases reported worldwide

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    Pulmonary alveolar microlithiasis (PAM) is a rare disease characterised by the widespread intra-alveolar accumulation of minute calculi called microliths. It is caused by mutation of the SLC34A2 gene encoding the type IIb sodium phosphate cotransporter in alveolar type II cells. The present study explores the epidemiological, familial, genetic, clinical, diagnostic, radiological and therapeutic aspects with the aim of contributing to a better understanding of this uncommon disease. We searched articles on PAM published up to December 2014 and 544 papers were found, accounting for 1022 cases. PAM is present in all continents and in many nations, in particular in Turkey, China, Japan, India, Italy and the USA. Familiality is frequent. The clinical course is not uniform and the causes of this clinical variability seem to be largely nongenetic. The optimal diagnostic procedure is the association of chest high-resolution computed tomography (HRCT) with bronchoalveolar lavage, but a chest radiograph may suffice in families in which a case has already been diagnosed. Moreover, chest radiography and HRCT allow the classification of the evolutionary phase of the disease and its severity. At present lung transplantation is the only effective therapy. However, better knowledge of the gene responsible offers hope for new therapies

    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

    Prenatal diagnosis of Pfeiffer syndrome and role of three-dimensional ultrasound: case report and review of literature

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    Purpose/aim of the study: We report a rare case of autosomal dominant genetic syndrome "Pfeiffer", which is part of the group of acrocephalosyndactyly, with an annual incidence <1/100,000. Three forms are known. Type I is the less common form and it is characterized by moderate-severe mediofacial hypoplasia usually with normal cognitive development. Conversely, types 2 and 3 are more common and they are associated with more severe signs and complications with a more unfavorable prognosis. The type 3 form due to the presence of a cloverleaf skull distinguishes type 2. Materials and methods: Thirty-eight-year-old primigravida was referred to our center, at 28 weeks of gestation due to borderline ventriculomegaly, macrocrania, and a short femur. First trimester screening for chromosomopathies and CF-DNA was low risk; II trimester screening ultrasound showed the presence of "short femur" and macrocrania. Result: Our ultrasound evaluation, assisted by 3D ultrasound, showed cloverleaf skull, turricephaly, moderate ventriculomegaly (13 mm), hypertelorism and exophthalmos, low ear implantation, mild rhizomelia. Ultrasound depicts Pfeiffer syndrome or other acrocephalosyndactyly syndromes (Apert syndromes, Saethre-Chotzen) or other syndromic forms of craniosynostosis like Crouzon syndrome. The NGS panel for molecular analysis of genes involved in skeletal dysplasias showed the mutation of the FGFR2 gene, de novo. Conclusions: Using three-dimensional (3D) ultrasound, it is easier to distinguish rare syndromes characterized by facial dysmorphisms such as exophthalmos, mediofacial hypoplasia, and craniosynostosis

    Clinical phenotype of the 16p.13.11 microdeletion: a case report with a mini review of the literature

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    Background: Chromosome 16p13.11 microdeletion is a very rare copy number variant (CNV), associated with a clinical syndrome characterized by global development delay, neuropsychiatric conditions, facial dysmorphisms, microcephaly, gastroesophageal reflux disease, and congenital heart defects. The 16p13.11 locus is a very unstable genomic region, rich in low-copy number repeats, characterized by many homologous DNA sequences. Usually, the most common CNV of this region include microduplications/duplications, while the microdeletions are rare, and their clinical features are heterogeneous and poorly described so far. Case report: In this paper, we report the genetic and the clinical features of a patient diagnosed with chromosome 16p13.11 microdeletion, and a short review of the literature on this topic. Our patient was characterized by several facial dysmorphic features, autistic symptoms and language development delay. The genetic evaluation revealed and interstitial deletion of the long arm of the chromosome 16, approximately of 1.5 Mb. Conclusion: Interestingly, compared to previous cases, this patient was characterized by autistic symptoms, severe language and motor coordination disorder, without cognitive and cerebral malformations, frequently associated with this microdeletion syndrome

    The first case of a small supernumerary marker chromosome derived from chromosome 10 in an adult woman with an apparently normal phenotype

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    Small supernumerary marker chromosomes (sSMCs) originating from chromosome 10 are rare. A limited number of cases are documented. We report a new diagnosis of a mosaic sSMC (10) in a normal female who asked for genetic evaluation before undergoing controlled ovarian hyperstimulation, in vitro fertilization, and embryo transfer. Chromosome preparations from peripheral lymphocyte cultures were performed according to standard procedures. QFQ-banded chromosomes confirmed the presence of an sSMC: 47,XX,+mar[49]/46,XX[51]. FISH and array CGH analysis showed that the sSMC consisted of chromosome 10 with a gain of the 10p11.1p11.21 (2.5 Mb) chromosomal region. The presence of sSMC (10) was also confirmed in the patient's mother and sister. It did not appear to affect the phenotype of the women who were phenotypically normal and healthy, and at the time of writing the woman became pregnant naturally. Phenotypes associated with an sSMC vary from normal to severely abnormal. It has been shown that variations in the chromosomal region of sSMCs result in observable differences in clinical outcome. The phenotypical consequences of sSMCs are difficult to predict because of differences in euchromatic DNA content, chromosomal origin, and varying degrees of mosaicism. Therefore, the continued investigation of a larger number of sSMC cases, in particular those originating from chromosome 10 that are the infrequently encountered and characterized, and a better understanding of the genetic content is important in order to improve the delineation of karyotype-phenotype correlation, contributing to a more informed prenatal counseling or prognosis

    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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