1,720,976 research outputs found
Vascularized Deinnvervated Muscle Target for motor unit based prosthetic limb control
No full textThis thesis focuses on addressing the significant challenges faced by individuals with traumatic limb loss in prosthetic limb control. Chapter 1 provides a comprehensive review of current neural prosthetic technologies, setting the foundation for subsequent research. Chapter 2 introduces the general methods employed throughout the thesis.
Chapter 3, the centerpiece of the thesis, investigates the natural bio-separator effect on vascularized denervated muscle targets (VDMT) to assess its potential for muscle reinnervation. This exploration aims to uncover insights into the physiological mechanisms underlying muscle reinnervation post-amputation, offering valuable guidance for prosthetic interventions. Building upon the findings from Chapter 3, Chapter 4 presents a novel approach termed Bi-VDMT, which involves surgically separating the tibial nerve and implanting them on different sites of the VDMT to enhance muscle reinnervation. Lastly, Chapter 5 addresses a crucial limitation in current wireless communication platforms for implantable reinnervated muscle systems—the transmission bandwidth—by investigating the impact of wavelet compression and electrode placement strategies on motor unit information preservation. Collectively, this multi-chapter investigation contributes to advancing the field of prosthetics by offering both theoretical insights and practical solutions aimed at improving the functionality and usability of prosthetic devices for individuals with limb loss
Vascularized Deinnvervated Muscle Target for motor unit based prosthetic limb control
No full textThis thesis focuses on addressing the significant challenges faced by individuals with traumatic limb loss in prosthetic limb control. Chapter 1 provides a comprehensive review of current neural prosthetic technologies, setting the foundation for subsequent research. Chapter 2 introduces the general methods employed throughout the thesis.
Chapter 3, the centerpiece of the thesis, investigates the natural bio-separator effect on vascularized denervated muscle targets (VDMT) to assess its potential for muscle reinnervation. This exploration aims to uncover insights into the physiological mechanisms underlying muscle reinnervation post-amputation, offering valuable guidance for prosthetic interventions. Building upon the findings from Chapter 3, Chapter 4 presents a novel approach termed Bi-VDMT, which involves surgically separating the tibial nerve and implanting them on different sites of the VDMT to enhance muscle reinnervation. Lastly, Chapter 5 addresses a crucial limitation in current wireless communication platforms for implantable reinnervated muscle systems—the transmission bandwidth—by investigating the impact of wavelet compression and electrode placement strategies on motor unit information preservation. Collectively, this multi-chapter investigation contributes to advancing the field of prosthetics by offering both theoretical insights and practical solutions aimed at improving the functionality and usability of prosthetic devices for individuals with limb loss
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
Corrigendum to 'Multidisciplinary strategies to treat painful mononeuropathies in the upper extremity: from lab to bedside’(J Hand Surg Eur., 10.1177/17531934241240389)
No full textThe name of the author J. Henk Coert was incorrect in the original paper. The name has now been corrected in the paper
REGENERATIVE BIONICS: INCORPORATING REINNERVATED MUSCLE INTO BIONIC SYSTEMS FOR PROSTHESIS CONTROL
Full text linkWithin the field of neuroprosthetics, there is a growing use of reinnervated muscle as a component in bionic systems for prosthesis control. Its popularity is due mainly to the pain relief benefits of muscle reinnervation, but it also offers the bio-amplification of nerve signals if the reinnervated muscle can be recorded from long-term. There are many varieties of bionic interfaces available for normal muscle tissue, but there does not yet exist an interface designed based on the unique physiology of muscle tissue that has had to regenerate and recover from major surgical intervention. Or from a different perspective, is it possible to optimize the surgical construction of a denervated muscle target (DMT) such that it is guaranteed to generate the most effective control signals?
After performing a pilot study of how differently sized DMTs might function after reinnervation, I developed and validated a versatile rat model of reinnervation using the soleus muscle and tibial nerve. This model is improved compared to the most commonly used model in the DMT field (which transects the peroneal nerve) because it is not debilitating to the animal. Using my model, I studied how completely devascularized DMTs regenerate their vasculature over time. This was motivated by the apparent gap in the scientific literature describing the 3D vascular regeneration patterns of muscle autografts. Finally, I studied how the same DMTs revascularize when there is a surface electrode present, which surprisingly showed little difference from DMTs with no electrode substrate. In summary, Part 1 of this thesis focuses on the electrophysiology of DMTs and how they could be constructed to maximize signal potential, and Part 2 focuses on the vasophysiology of DMTs healing immediately post surgery and how certain bionic hardware might influence regeneration.
Future research that builds off of my work should focus on the marriage of 3D tissue imaging data with chronic electromyography data. Further understanding the relationship between regenerating tissue structure and its long-term function will allow us to build new models that could predict how different DMTs will behave over time based on their unique anatomy
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