1,720,985 research outputs found
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
Early sleep after action observation and motor imagery training boosts improvements in manual dexterity
Full text link: The systematic observation and imagination of actions promotes acquisition of motor skills. Furthermore, studies demonstrated that early sleep after practice enhances motor learning through an offline stabilization process. Here, we investigated behavioral effects and neurodynamical correlates of early sleep after action observation and motor imagery training (AO + MI-training) on motor learning in terms of manual dexterity. Forty-five healthy participants were randomized into three groups receiving a 3 week intervention consisting of AO + MI-training immediately before sleeping or AO + MI-training at least 12 h before sleeping or a control stimulation. AO + MI-training implied the observation and motor imagery of transitive manual dexterity tasks, whereas the control stimulation consisted of landscape video-clips observation. Manual dexterity was assessed using functional tests, kinematic and neurophysiological outcomes before and after the training and at 1-month follow-up. AO + MI-training improved manual dexterity, but subjects performing AO + MI-training followed by early sleep had significantly larger improvements than those undergoing the same training at least 12 h before sleeping. Behavioral findings were supported by neurodynamical correlates during motor performance and additional sleep-dependent benefits were also detected at 1 month follow-up. These findings introduce a new approach to enhance the acquisition of new motor skills or facilitate recovery in patients with motor impairments
EEG connectivity in functional brain networks supporting visuomotor integration processes in dominant and non-dominant hand movements
No full text: Objective.This study explores the changes in the organization of functional brain networks induced by performing a visuomotor integration task, as revealed by noninvasive spontaneous electroencephalographic traces (EEG).Approach.EEG data were acquired during the execution of the Nine Hole Peg Test (NHPT) with the dominant and non-dominant hands in a group of 44 right-handed volunteers. Both spectral analysis and phase-based connectivity analysis were performed in the theta (θ), mu (μ) and beta (ß) bands. Graph Theoretical Analysis (GTA) was also performed to investigate the topological reorganization induced by motor task execution.Main results.Spectral analysis revealed an increase of frontoparietal θ power and a spatially diffused reduction ofμand ß contribution, regardless of the hand used. GTA showed a significant increase in network integration induced by movement performed with the dominant limb compared to baseline in the θ band. Theμand ß bands were associated with a reduction in network integration during the NHPT. In theμrhythm, this result was more evident for the right-hand movement, while in the ß band, results did not show dependence on the laterality. Finally, correlation analysis highlighted an association between frequency-specific topology measures and task performance for both hands.Significance.Our results show that functional brain networks reorganize during visually guided movements in a frequency-dependent manner, differently depending on the hand used (dominant/non dominant)
Heart lipid accumulation in obese non-diabetic rats: Effect of weight loss.
No full textBACKGROUND AND AIM: The aim of this study was to investigate lipid content and expression of genes involved in lipid metabolism, in lean and obese non-diabetic rats and in obese rats undergoing food restriction and weight loss.
METHODS AND RESULTS: We studied lean and genetically obese Zucker rats (fa/fa). Another group of obese rats were food restricted to lose 20% of initial body weight. We measured expression of genes involved in lipid oxidation and synthesis. Tissue triglyceride content, cell apoptosis and tissue fibrosis were also evaluated. The hearts of obese rats have higher triglyceride content compared to lean controls despite an increased expression of genes involved in fatty acid oxidation (PPAR alpha, PGC-1 alpha, CPT-I, ACO, UCP3). No differences were found in apoptosis and tissue fibrosis between the two phenotypes. Weight loss resulted in a significant reduction in heart lipid content, while the expression of genes involved in fatty acid oxidation remained elevated.
CONCLUSION: In contrast to data reported in diabetic rats, pathways of lipid oxidation are increased rather than decreased in insulin-resistant obese rats. Food restriction reduced heart triglyceride content while lipid-oxidizing genes remained elevated, probably as a consequence of lipid oversupply coming from the endogenous source
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
Heart lipid accumulation in obese non-diabetic rats: Effect of weight loss
No full textBACKGROUND AND AIM: The aim of this study was to investigate lipid content and expression of genes involved in lipid metabolism, in lean and obese non-diabetic rats and in obese rats undergoing food restriction and weight loss.
METHODS AND RESULTS: We studied lean and genetically obese Zucker rats (fa/fa). Another group of obese rats were food restricted to lose 20% of initial body weight. We measured expression of genes involved in lipid oxidation and synthesis. Tissue triglyceride content, cell apoptosis and tissue fibrosis were also evaluated. The hearts of obese rats have higher triglyceride content compared to lean controls despite an increased expression of genes involved in fatty acid oxidation (PPAR alpha, PGC-1 alpha, CPT-I, ACO, UCP3). No differences were found in apoptosis and tissue fibrosis between the two phenotypes. Weight loss resulted in a significant reduction in heart lipid content, while the expression of genes involved in fatty acid oxidation remained elevated.
CONCLUSION: In contrast to data reported in diabetic rats, pathways of lipid oxidation are increased rather than decreased in insulin-resistant obese rats. Food restriction reduced heart triglyceride content while lipid-oxidizing genes remained elevated, probably as a consequence of lipid oversupply coming from the endogenous source
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
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