1,720,998 research outputs found
Tutorial. Surface EMG detection, conditioning and pre-processing: Best practices
Full text linkThis tutorial is aimed primarily to non-engineers, using or planning to use surface electromyography (sEMG) as
an assessment tool for muscle evaluation in the prevention, monitoring, assessment and rehabilitation fields. The
main purpose is to explain basic concepts related to: (a) signal detection (electrodes, electrode–skin interface,
noise, ECG and power line interference), (b) basic signal properties, such as amplitude and bandwidth, (c)
parameters of the front-end amplifier (input impedance, noise, CMRR, bandwidth, etc.), (d) techniques for interference
and artifact reduction, (e) signal filtering, (f) sampling and (g) A/D conversion, These concepts are
addressed and discussed, with examples.
The second purpose is to outline best practices and provide general guidelines for proper signal detection,
conditioning and A/D conversion, aimed to clinical operators and biomedical engineers. Issues related to the
sEMG origin and to electrode size, interelectrode distance and location, have been discussed in a previous tutorial.
Issues related to signal processing for information extraction will be discussed in a subsequent tutorial
Biodiversità in Tuber aestivum e Tuber aestivum var. uncinatum mediante analisi isoenzimatiche
No full textSalt tolerance in safflower (Carthamus tinctorius L.) genotypes selected through proton extrusion activity method.
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Design and Characterization of a Textile Electrode System for the Detection of High-Density sEMG
Full text linkMuscle activity monitoring in dynamic conditions is a crucial need in different scenarios, ranging from sport to rehabilitation science and applied physiology. The acquisition of surface electromyographic (sEMG) signals by means of grids of electrodes (High-Density sEMG, HD-sEMG) allows obtaining relevant information on muscle function and recruitment strategies. During dynamic conditions, this possibility demands both a wearable and miniaturized acquisition system and a system of electrodes easy to wear, assuring a stable electrode-skin interface. While recent advancements have been made on the former issue, detection systems specifically designed for dynamic conditions are at best incipient. The aim of this work is to design, characterize, and test a wearable, HD-sEMG detection system based on textile technology. A 32-electrodes, 15 mm inter-electrode distance textile grid was designed and prototyped. The electrical properties of the material constituting the detection system and of the electrode-skin interface were characterized. The quality of sEMG signals was assessed in both static and dynamic contractions. The performance of the textile detection system was comparable to that of conventional systems in terms of stability of the traces, properties of the electrode-skin interface and quality of the collected sEMG signals during quasi-isometric and highly dynamic tasks
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
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