1,721,164 research outputs found
The role of the corpus callosum and bilaterally distributed motor pathways in the synchronization of bilateral upper-limb responses to lateralized light stimuli
No full text(from the book) [the authors] review their work on reaction times for simple responses using axial, proximal, and distal muscles of the upper limbs in normal Ss and Ss with callosal deficit / demonstrate that the time needed for interhemispheric integration of crossed responses becomes much larger in patients with a callosal deficit and this is the case for unilateral and bilateral distal responses and unilateral proximal responses / it is inferred from these findings that the intact corpus callosum allows for efficient interhemispheric communication in order to secure integration of these responses / however, when proximal bilateral responses and unilateral and bilateral axial responses are made, other pathways are hypothesized to be responsible for integration / argue that a bilaterally distributed motor system secures the production of these symmetrical movements involving axial and proximal limb muscles, and this system can be called upon by each of both hemisphere
Representation of Wrist Joint Kinematics by the Ensemble of Muscle Spindles From Synergistic Muscles
No full text Verschueren, Sabine M. P., Paul J. Cordo, and Stephan P. Swinnen. Representation of wrist joint kinematics by the ensemble of muscle spindles from synergistic muscles. J. Neurophysiol. 79: 2265–2276, 1998. Proprioceptive information about movement is transmitted to the central nervous system by a variety of receptor types, which are widely distributed among the muscles, joints, and skin. Muscle spindles are known to be an important and reliable source of information for the perception of movement kinematics. Previous studies that focused on the characteristics of single muscle spindle firing patterns have left the impression that each receptor fires in relation to a number of kinematic variables, leaving the following question unanswered: what role is played by the ensemble of muscle spindles within the same muscle or within synergistic muscles? The study described in this paper addressed whether the perception of joint position and velocity is based on the net input of muscle spindles residing in all synergistic muscles crossing a joint. Normal human adults performed a motor coordination task that required perception of joint velocity and dynamic position at the wrist. The task was to open the left hand briskly as the right wrist was passively rotated in the flexion direction through a prescribed target angle. In randomly occurring trials, the tendons to three muscles [extensor carpi radialis (ECR), extensor carpi ulnaris (ECU), and extensor digitorum (ED)] were vibrated either individually or in different combinations during the performance of the motor task. Tendon vibration is known to distort muscle spindle firing patterns, and consequently, kinesthesia. By comparing performance errors with and without tendon vibration, the relative influences of muscle spindles residing in ECR, ECU, and ED were quantified. Vibration of the individual ECR, ECU, or ED tendons produced systematic undershoot errors in performance, consistent with the misperception of wrist velocity and dynamic position. Performance errors were larger when combinations of, rather than individual, muscle tendons were vibrated. The error resulting from simultaneous vibration of ECR and ECU was roughly equal to the sum of the errors produced by vibration of the individual tendons. These effects of vibrating synergistic tendons at the wrist suggest that kinesthesia is derived from the integrated input of muscle spindles from all synergistic muscles. </jats:p
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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