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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
The arterial anatomy of the eyelid: importance for reconstructive and aesthetic surgery
No full textPurpose: The aim of the study was to investigate the arterial distribution of the eyelids. Methods: The location, course, length and diameter of eyelid arteries were determined in 19 preserved and latex injected adult mate cadaver heads. Results: The diameter of the medial. palpebral. artery was found to be 1.50 +/- 0.28 mm on the right, and 0.70 +/- 0.12 mm on the left. The diameter of the lateral palpebral artery was measured as 0.62 +/- 0.10 mm on the right, and 0.59 +/- 10.12 mm on the left. The medial palpebral. arteries travelling in the medial part of the eyelids usually arose as separate branches for the upper and lower lids, as superior and inferior medial. palpebrals. In all cases, four arterial arcades, the marginal, peripheral, superficial orbital, and the deep orbital arcades, were revealed in the upper palpebra. These arterial arcades gave off small perforating branches. The perforating branches were identified on both sides of the tarsal plate and the orbicularis muscle. In four cases (11%) visible arterial variation was found near the inferotateral, end of the levator palpebrae. Although many differences in the arterial features of the eyelid have been noted, there may not be a significant difference in the basic vasculature of the palpebra among races. A better understanding of the palpebral vascularity should allow modification of reconstructive techniques and reduce postoperative complications after eyelid surgery. (c) 2006 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved
Asterion as a surgical landmark for lateral cranial base approaches
No full textIntroduction: When approaching the posterior fossa and posterolateral cranial base, surface landmarks are helpful in locating the junction of the transverse and the sigmoid sinus. Material and methods: On 100 skull halves a 2 mm drill bit was externally placed over the asterion and was drilled through the bone perpendicular to the skull surface. Various positions of the asterion and its distance from the root of the zygomatic process of the temporal bone, from the suprameatal crest and the mastoid tip were investigated. Results: The position of the asterion has been found to be located superficial to the transverse-sigmoid sinus junction in 87% of all samples, inferior to the transverse-sigmoid sinus junction in 11% and superior to the transverse-sigmoid sinus junction in 2%. The distance from the asterion to the root of the zvgoma has been determined to be 54.6 +/- 5.5 mm. The distance between asterion and Henle's spine was 45.2 +/- 5.2, and from asterion to Frankfurt Horizontal Plane 15 +/- 7.5 mm. Conclusion: Asterion varies regarding its cephalocaudal position. The findings of this study might have direct consequences for transmastoid and retrosigmoid approaches for microvascular trigeminal root decompression and combined petrosal approaches. (C) 2006 European Association for Cranio-Maxillofacial Surgery
Anatomic Characteristics of the Ophthalmic and Posterior Ciliary Arteries
No full textBackground: There is little documentation of the course and relations of the ophthalmic artery (OA) and posterior ciliary arteries (PCAs). Methods: The anatomic characteristics of the OA and PCAs were determined from a dissection of 19 neoprene-injected cadaver heads. Results: The intraorbital OA had three segments, considering its relation to the optic nerve in the sagittal plane. The first segment extended from the point where the OA entered the orbit to its curving point. The second segment coursed superomedially from the inferolateral part of the optic nerve, crossing the optic nerve either superiorly or inferiorly. The third segment extended from the curving point of the superomedial distal portion of the second segment to the vessel's termination. The OA was deviated at the junction of its first and second segments, defined as its "angle"; and at the junction of the second and third segments, defined as its "bend." The PCAs arose from the first OA segment, the angle of the OA, the second OA segment and the OA bend. The patterns of branching of the PCAs were medial and lateral and medial, lateral, and superior. The superior PCA and the lateral PCA arose mainly from the angle of the OA, whereas the medial PCA arose from the curving point of the OA. The most frequently observed PCA pattern was a medial PCA and a lateral PCA. The average diameters of the medial PCA, the superior PCA, and the lateral PCA were 0.65, 0.48, and 0.68 mm, respectively. In all cases, pial arteries branching from the PCA and supplying the optic sheath were observed to form a vascular plexus on the optic sheath. The OA and PCAs were surrounded by a network of sympathetic nerves. Conclusions: Because the most common pattern of PCAs is a medial and lateral branch, a surgical approach to the orbit from those directions carries a higher risk of damage to those vessels than a superior or inferior approach
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
Anatomy of the supraorbital region and the evaluation of it for the reconstruction of facial defects
No full textDamaged supraorbital neurovascular bundle during anterior orbital approach, fronto-glabellar reconstruction flap, supraorbital injection, blepharospasm, and Graves disease surgery is an important complication reported with varying frequency. The origin, calibration, and branches of the supraorbital artery and its topographical relations were investigated by injection of the arterial bed with red-dyed latex in 38 forehead regions. The supraorbital artery with the supratrochlear artery arose from the orbit as two separate vessels in 33 out of 38 forehead sides (87%). The supraorbital artery entered the frontalis muscle between 20 and 30 mm in 20 cases (52.6%), and between 30 and 40 mm in 16 cases (42.1%). This artery was located approximately the subcutaneous tissues between 40 and 50 mm in 17 cases (44.7%), between 50 and 60 mm in 18 cases (47.4%). The transverse supraorbital vein coursed at the level of the orbital rim on 22 sides (58%) and between 6.1 and 11.2 mm (mean: 9.4 mm) above the supraorbital rim on 16 sides (42%). All branches of supraorbital nerve were located between 2.0 and 3.2 cm from the midline at the level of the orbital rim. In 23 cases (60%), the lateral branch of the supraorbital nerve exited the bone as two branches, usually one large and one much smaller, which can together run into the scalp without further branching. In the present anatomical study, special attention was paid to morphological details concerning the neurovascular relationship of the supraorbital region. A better understanding of the midline forehead neurovascularity should allow modification of reconstructive techniques, afford better localization of the supraorbital nerve during blepharoplasty and ptosis surgery, and reduce the incidence of postoperative hematomas and nerve injuries
Anatomical considerations of safe drilling corridor upper sacral segment screw insertion
No full textBagheri, Hassan/0000-0002-6126-9543The upper segment of sacrum is an important for screw insertions of unstable lumbosacral spine. Measurements of the S1-S2 as sacral wings, pedicles, sacral foraminas and sacral canal were taken from 87 sacrums. the mean depths of S1 pedicle and sacral wing were estimated as 25.8 +/- 2.3 mm and 50.1 +/- 1.7 mm, respectively. Angles screw trajectory of sacral pedicle anteromedial and sacral wing were measured as 29.6 +/- 0.9 degrees and 29.7 +/- 2.1 degrees, respectively. To avoid injury to the vascular structures anteriorly and nerve roots medially, depth and angle of screw trajectory is important for the entrance off pedicular screw placement to the S1
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
Arterial features of inner canthus region: Confirming the safety for the flap design
No full textThe medial canthus represents a fixed-point fulcrum that is necesarry for eyelid function. The aim of the study was to investigate the arterial distribution of the inner canthus. The origin, calibration, and branches of the inner canthus arteries and their topographical relations were examined by dissecting 19 cadavers, injecting red latex to their corresponding 38 nasal sections before the dissection. The distance from the dorsal nasal artery to the inner canthus was found to be 7.2 +/- 0.3 mm. In this study, the average diameter of the dorsal nasal artery was 0.74 mm on the right side and 0.88 mm on the left. Concerning the course of dorsal nasal artery on the lateral side of the nose, 4 types were observed. In most of the examples (44.7%), dorsal nasal artery anastomosed with angular artery via thick branch and gave off supplying branches to the medial canthus and to the lateral side of the nose. Dorsal nasal artery is a vessel of satisfactory size and is potentially a good vascular source for a thin free flap. It may be an ideal flap to reconstruct the eyelid defect for texture and color similarity of the inner canthus skin. A better understanding of the inner canthus vascularity should allow modification of reconstructive techniques and reduce postoperative complications
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