1,721,183 research outputs found
Do sperm cells remember?
No full textSpontaneous alternation behavior (SAB) is the universal tendency of animals, including unicellular organisms, to alternate directional choices at consecutive left/right branchings while traversing a maze. Occurrence of SAB implies short-term memory, as a current decision is statistically dependent on previous ones. We developed a procedure to assess SAB in human spermatozoa. A total of 1302 progressively motile spermatozoa from healthy donors were observed as they entered one of two mazes, both fabricated by eximer laser ablation. The control maze was a simple T-maze (width = depth = 20 mum, distance between entrance and free choice T-intersection = 600 mum). The experimental maze was identical to the control maze except for a forced right-turn 600 mum before the T-intersection. We recorded individual sperm cells' left/right decisions at the T-intersections in both mazes. Of the 714 spermatozoa entering the control maze, 49.1% turned to the left (not significantly different from the chance expectation of 50.0%). Of the 588 spermatozoa entering the experimental maze, 58.6% turned left after the initial forced right turn (significant SAB, P=0.041, Wilcoxon). The statistical dependency of a directional decision on a previous one suggests a physiological 'memory' in human spermatozoa. Among the possible underlying mechanisms are refractory processes in structures responsible for flagellar beating, a postulation which deserves further scrutiny with video-monitored single-cell testing. (C) 2002 Elsevier Science B.V. All rights reserved
Is the desire for amputation related to disturbed emotion processing? A multiple case study analysis in BIID
Get PDFBody integrity identity disorder (BIID) is characterized by the overwhelming desire to amputate one or more healthy limbs or to be paraplegic. Recently, a neurological explanation of this condition has been proposed, in part on the basis of findings that the insular cortex might present structural anomalies in these individuals. While these studies focused on body representation, much less is known about emotional processing. Importantly, emotional impairments have been found in psychiatric disorders, and a psychiatric etiology is still a valid alternative to purely neurological accounts of BIID. In this study, we explored, by means of a computerized experiment, facial emotion recognition and emotional responses to disgusting images in seven individuals with BIID, taking into account their clinical features and investigating in detail disgust processing, strongly linked to insular functioning. We demonstrate that BIID is not characterized by a general emotional impairment; rather, there is a selectively reduced disgust response to violations of the body envelope. Taken together, our results support the need to explore this condition under an interdisciplinary perspective, taking into account also emotional connotations and the social modulation of body representation
Mental representations of (phantom) body parts
No full textBläsing B, Schack T, Brugger P. Mental representations of (phantom) body parts. In: Urbas L, Goschke T, Velichkowsky B, eds. Tagungsband der 9. Fachtagung der Gesellschaft für Kognitionswissenschaft. 2008: 66
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
Körperrepräsentation und der Einsatz von (Phantom-) Gliedmaßen
No full textBläsing B, Schack T, Brugger P. Körperrepräsentation und der Einsatz von (Phantom-) Gliedmaßen. In: Sudek G, Conzelmann A, Lehnert K, Gerlach E, eds. Differentielle Sportpsychologie - Sportwissenschaftliche Persönlichkeitsforschung. Vol 176. Hamburg: Czwalina Verlag; 2008: 28
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
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
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