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Posterior arch defect of the atlas associated to absence of costal element of foramen transversarium from 16th century Sardinia (Italy)
Full text linkStudy Design. A paleopathological case of posterior arch defect of the atlas associated to the absence of costal element of the foramen transversarium.
Objective. In living patients as well as in postmortem analysis it should be difficult to distinguish between a congenital and an acquired anomaly. Any anomaly in the anatomy of atlas should be taken into consideration by clinicians, surgeons, radiologists, and anatomists in order to avoid misinterpretations and clinical complications.
Summary of Background Data. Posterior arch defect has a current occurrence of approximately 4%. Posterior arch schisis is attributed to the defective or absent development of the cartilaginous preformation of the arch rather than a disturbance of the ossification. The absence of costal element of the foramen transversarium has an incidence of ranging from 2% to 10% and is attributed to a developmental defect or to variations in the
course of the vertebral artery.
Methods. The skeleton of a man aged 20–30 years, brought to
light in the plague cemetery of 16th century Alghero (Sardinia),
showed anomalies of the atlas, consisting in failure of the
midline fusion of the 2 hemiarches with a small gap and
an open anterior foramen trasversarium on the left side. A
macroscopic, radiological, and stereomicroscopic study was carried out.
Results. The study allowed to rule out a traumatic origin of the defects and to diagnose an association of 2 congenital anomalies.
Conclusion. Osteoarchaeological cases provides with a valuable opportunity to examine and describe variations in the anatomy of the atlas
Anatomical variations in ancient sardinian populations
No full textArchaeological excavations carried out in different burial sites of north-western Sardinia allowed to observe anatomical variations in ancient skeletal remains. A case of brachymetatarsia, consisting of bilateral abnormal shortness of the fourth metatarsal bone, was detected in an adult female uncovered from the Medieval village of Geridu (Sassari), dated back to the late 13th or the first half of the 14th century; such a rare deformity has a clinical incidence of 0.02% to 0.05% (1).
Several anatomical variations were diagnosed in individuals brought to light from the plague cemetery of 16th century Alghero (Sassari). The skeleton of a 9-10-year-old child showed a skull malformation due to premature bilateral closure of the coronal suture, diagnosed as non-syndromic brachycephaly (2). Posterior schisis of the first cervical vertebra, consisting of failure of the midline fusion of the two hemiarches with a small gap, was seen in a male aged 20-30 years; this type of anomaly has a current occurrence of approximately 4%. Occipitalization of the atlas associated with posterior spondiloschisis was observed in a male aged 35-45 years. There is complete fusion of the superior articular facets of the first cervical vertebra with the occipital condyles; this congenital anomaly has a current incidence of 0.14 to 0.75% of the population.
The small number of published osteoarchaeological cases of anatomical variations makes any report important
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
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
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
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