262,188 research outputs found

    Increased Bilateral Interactions in Middle-Aged Subjects

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    A hallmark of the age-related neural reorganization is that old versus young adults execute typical motor tasks by a more diffuse neural activation pattern including stronger ipsilateral activation during unilateral tasks. Whether such changes in neural activation are present already at middle age and affect bimanual interactions is unknown. We compared the amount of associated activity, i.e., muscle activity and force produced by the non-task hand and motor evoked potentials (MEPs) produced by magnetic brain stimulation between young (mean 24 years, n = 10) and middle-aged (mean 50 years, n = 10) subjects during brief unilateral (seven levels of % maximal voluntary contractions, MVCs) and bilateral contractions (4 × 7 levels of % MVC combinations), and during a 120-s-long MVC of sustained unilateral index finger abduction. During the force production, the excitability of the ipsilateral (iM1) or contralateral primary motor cortex (cM1) was assessed. The associated activity in the “resting” hand was ~2-fold higher in middle-aged (28% of MVC) versus young adults (11% of MVC) during brief unilateral MVCs. After controlling for the background muscle activity, MEPs in iM1 were similar in the two groups during brief unilateral contractions. Only at low (bilateral) forces, MEPs evoked in cM1 were 30% higher in the middle-aged versus young adults. At the start of the sustained contraction, the associated activity was higher in the middle-aged versus young subjects and increased progressively in both groups (30 versus 15% MVC at 120 s, respectively). MEPs were greater at the start of the sustained contraction in middle-aged subjects but increased further during the contraction only in young adults. Under these experimental conditions, the data provide evidence for the reorganization of neural control of unilateral force production as early as age 50. Future studies will determine if the altered neural control of such inter-manual interactions are of functional significance

    Weight dependent modulation of motor resonance induced by weight estimation during observation of partially occluded lifting actions

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    Seeing others performing an action induces the observers' motor cortex to "resonate" with the observed action. Transcranial magnetic stimulation (TMS) studies suggest that such motor resonance reflects the encoding of various motor features of the observed action, including the apparent motor effort. However, it is unclear whether such encoding requires direct observation or whether force requirements can be inferred when the moving body part is partially occluded. To address this issue, we presented participants with videos of a right hand lifting a box of three different weights and asked them to estimate its weight. During each trial we delivered one transcranial magnetic stimulation (TMS) pulse over the left primary motor cortex of the observer and recorded the motor evoked potentials (MEPs) from three muscles of the right hand (first dorsal interosseous, FDI, abductor digiti minimi, ADM, and brachioradialis, BR). Importantly, because the hand shown in the videos was hidden behind a screen, only the contractions in the actor's BR muscle under the bare skin were observable during the entire videos, while the contractions in the actor's FDI and ADM muscles were hidden during the grasp and actual lift. The amplitudes of the MEPs recorded from the BR (observable) and FDI (hidden) muscle increased with the weight of the box. These findings indicate that the modulation of motor excitability induced by action observation extends to the cortical representation of muscles with contractions that could not be observed. Thus, motor resonance appears to reflect force requirements of observed lifting actions even when the moving body part is occluded from view

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Neuronal mechanisms of motor learning and motor memory consolidation in healthy old adults

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    It is controversial whether or not old adults are capable of learning new motor skills and consolidate the performance gains into motor memory in the offline period. The underlying neuronal mechanisms are equally unclear. We determined the magnitude of motor learning and motor memory consolidation in healthy old adults and examined if specific metrics of neuronal excitability measured by magnetic brain stimulation mediate the practice and retention effects. Eleven healthy old adults practiced a wrist extension-flexion visuomotor skill for 20 min (MP, 71.3 years), while a second group only watched the templates without movements (attentional control, AC, n = 11, 70.5 years). There was 40 % motor learning in MP but none in AC (interaction, p < 0.001) with the skill retained 24 h later in MP and a 16 % improvement in AC. Corticospinal excitability at rest and during task did not change, but when measured during contraction at 20 % of maximal force, it strongly increased in MP and decreased in AC (interaction, p = 0.002). Intracortical inhibition at rest and during the task decreased and facilitation at rest increased in MP, but these metrics changed in the opposite direction in AC. These neuronal changes were especially profound at retention. Healthy old adults can learn a new motor skill and consolidate the learned skill into motor memory, processes that are most likely mediated by disinhibitory mechanisms. These results are relevant for the increasing number of old adults who need to learn and relearn movements during motor rehabilitation

    Protecting Animals 36: Author Witi Ihimaera

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    In this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries

    Interaction between force production and cognitive performance in humans

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    Objective: A dual task paradigm was used to examine the effects of the generation of force on cognitive performance. Methods: Subjects (n = 22) were asked to respond to auditory stimuli with their left middle or index finger and concurrently maintain a sub-maximal contraction with their right index finger at one of two different force levels. The contraction was maintained for approximately 12 s and the target force level was alternated between 30 and 60% of the maximal force. Force production was the primary task of interest; performance of the (secondary) choice reaction time task (reaction times and accuracy) was used as an index of the amount of interference between the two tasks. Results: All subjects were capable of performing the force tasks adequately. Significant interference was observed between the level of force production and cognitive performance. At the higher force level, subjects performed the cognitive task more slowly and less accurately compared to the lower force level. Conclusion: Our results show that the execution of high-effort motor behaviour interacts with cognitive task performance. However, comparison with the data obtained during fatiguing contractions in a previous study [Lorist MM, Kernell D, Meijman TF, Zijdewind I. Motor fatigue and cognitive task performance in humans. J Physiol 2002;545:313-319.] showed that the interference was stronger during fatiguing contractions than during the present high-effort motor behaviour. Significance: The results suggest that force-related factors can explain part of the fatigue-related interference between force production and cognitive performance. This result could have consequences for interpreting cognitive deficits observed in patients suffering from motor dysfunction. (c) 2005 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved

    Author in Essay by I. A. Goncharov “Pepiniere”

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    Features of the embodiment of the author’s position in the essay by I. A. Goncharov “Pepiniere” are considered. The relevance of the study is due to the poorly studied poetics of this work. A review of the scientific literature on relevant topics is performed. Methodological and theoretical definitions are given. The scientific novelty of the article is in the fact that for the first time attention is paid to artistic techniques that allow to identify the author's position in the specified literary text. The author of the article grounds her opinion from the fact that, despite the dominance of the subjective point of view, other characters’ views stand out in the work. It is concluded in the study that the text of the work represents a biographical author and author-creator. It was established that the position of the author-creator is expressed through the title, epigraphs, which are quotes, as well as through different points of view, including the author-character, the author-narrator, the characters of the work. The author of the article dwells in detail on different ways of expressing the points of view of the author-character and the author-narrator. It is proved that the point of view of the author-character and the author-narrator can intersect, they are interchanged. The author's development of the term comic “point of view” is presented in the article

    Espai i identitat en l'obra de Jordi Pere Cerdà. Una geografia literària cerdaniana

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    L'obra de l'autor nord-català Jordi Pere Cerdà (1920-2011) teixeix una cartografia literària que abasta tota dimensió espacial -real, imaginada i ficcional. Les prospeccions que assagen els seus texts es fonen en el medi natural i rural, canten a l'amor, als veïns i als éssers fantàstics del folklore català, es comprometen amb els refugiats encarant-se a tota frontera i, també, a tot abisme interior i exterior que oprimesca l'ésser. El mapatge cognitiu i literari que crea Cerdà sobrepassa qualsevol obstacle per construir espais oberts i possibles, en comunió amb l'altre. Partint d'una aproximació teòrica geocrítica, aquest treball d'investigació aprofundeix en diverses nocions sobre l'espacialitat lligades a un context convuls, ple de transformacions a nivell socioeconòmic, polític, cultural i lingüístic, el qual determinarà la vida d'un autor i d'un territori transfronterer com el de la Cerdanya i la Catalunya del Nord. En definitiva, la rica experiència vital de Jordi Pere Cerdà ens permet reflexionar sobre les relacions que vulguem establir entre els individus i amb el nostre hàbitat natural i cultural, a fi d'esdevenir membres actius que participen de la transformació dels espais que configuren les nostres identitats.The work of the North Catalan author Jordi Pere Cerdà (1920-2011) weaves a literary cartography which reaches all spatial dimensions -real, imagined and fictional. The prospections proved by their texts merge with the natural and rural environment, sing to love, neighbours and the fantastic beings of the Catalan folklore. Such prospections also commit themselves with the refugees facing every frontier and, also, facing all interior and exterior abyss that oppresses the being. The cognitive and literary mapping created by Cerdà overcomes any obstacle to construct opened and possible spaces, in communion with the other. Based on the theoretical approach called geocriticism, this research study delves into various notions about spatiality linked to a convulsive context, full of transformations at a socioeconomic, political, cultural and linguistic level; these transformations will determine the life of an author and a cross-border territory such as Cerdagne and Northern Catalonia. In short, the rich experience of Jordi Pere Cerdà allows us to reflect on the relationships we want to establish between individuals, as well as between human groups and our natural and cultural habitat, in order to become active members that participate in the transformation of the spaces that make up our identities.Programa de Doctorat en Llengües Aplicades, Literatura i Traducci

    Els llibres d'il·lustració infantil i juvenil en l'Educació Artística. Un cas concret a partir de l’autora Olga de Dios

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    Treball Final de Grau en Mestre o Mestra d'Educació Primària (Pla de 2018). Codi: MP1840. Curs acadèmic: 2021/2022El treball de fi de grau que aneu a veure a continuació, és un projecte que consisteix en com es poden treballar a les aules de primària els llibres de l’autora i il·lustradora Olga de Dios. Tractant de treballar el llibre com a objecte artístic a nivell elemental. A més, de presentar a l’autora i il·lustradora, donarla a conèixer i veure els valors que transmet, també llegiríem quatre de les seues obres a l’aula com són: “Leotolda”, “En familia”, “Rana de Tres Ojos”, i “Pájaro Amarillo”. Tot açò sumat a la realització d’un quadern de classe on es colorejaria alguns dels seus personatges de les obres seguint pautes a nivell curricular. Realitzaríem també una eixida a la biblioteca municipal, on a banda de rebre una educació no formal, ens facilitaria una mica el fet d’endinsar-nos al món de la il·lustració infantil, on allí dins, el professional encarregat ens guiarà pels llibres que hi haurà a la biblioteca. I, per a concloure, elaboraríem un llibre creat per l’alumnat on seguint unes pautes establertes per Olga de Dios al seu llibre “Leotolda” buscaríem fer una retroalimentació intentant contactar amb ella. D’aquesta manera tancaríem el cicle que vam començar donant-la a conèixer com a escriptora i il·lustradora, i exploraríem on està el límit de la creativitat del propi alumnat.The final degree project you are going to see below is a project that looks at how books by author and illustrator Olga de Dios can be worked on in primary school classrooms. Considering the book as an artistic object at an elementary level. Besides presenting the author and illustrator, introducing her, and seeing the values she transmits, we would also read four of her works in the classroom, such as: "Leotolda”, "In the family", "Three-Eyed Frog", and "Yellow Bird.". All this, in addition to the creation of a class notebook in which some of his characters from her work would be colored following guidelines at the curricular level. We would also go out to the local library, where in addition to receiving a non-formal education, it would make it a little easier for us to enter the world of children's illustration, where inside, the professional in charge will guide us through the books which will be in the library. And, to conclude, we would make a book created by the students, where following some guidelines established by Olga de Dios in her book "Leotolda" we would look for feedback by trying to contact her. In this way, we would close the cycle that we started by presenting her as an author and illustrator, and we would explore where the limit of creativity of the students themselves is
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