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Results 651 - 681 of 681
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Matthews P B - - 1980
1. The tremor that develops when the elbow is flexed against a spring attached at the wrist has been analysed by determining the 'power' spectrum of the demodulated surface e.m.g. recorded from two of the active muscles, biceps and brachioradialis. This was compared with the corresponding force spectrum obtained by ...
Knutsson E - - 1980
Dynamic motor capacity was studied in 24 patients with spastic paraparesis (18 cases) or hemiparesis (6 cases). Torque was recorded with an isokinetic dynamometer in voluntary dynamic knee extensions and flexions at maximum effort and in passive movements at preset speeds of 30, 90 and 180 deg . s-1. EMG ...
Kocylowski M - - 1979
Electrical and mechanical activity were studied in the ex vivo total canine colon, supported in a perfusion chamber by a supporting dog. Regular electrical activity could be recognized visually in 50--70% of the records. The frequency of this activity was in the range of 7--10/min. Fourier analysis also revealed dominant ...
Betts B - - 1979
A real-time period-amplitude analysis program for EMG involving the detection of events consisting of the period and amplitude difference between maxima and minima was used to study the activity patterns of fast and slow, hind and forelimb extensors during treadmill locomotion and jumping. Events were stored in a two-dimensional table ...
Barclay J K - - 1979
Active stress, stress-time integral (STI) and total heat production of cat right ventricular papillary muscles were recorded during brief trains of isometric twitch contractions at muscle lengths less than or equal to optimal length. Individual muscles were subjected to a 10 degree C change in temperature, a change of stimulus ...
Hallett M - - 1979
1. In response to an auditory stimulus normal subjects made ballistic flexion movements of the top joint of the thumb against a lever attached to the spindle of a low-inertia electric motor. 2. Electromyographic (e.m.g.) activity was recorded from pairs of fine wire electrodes inserted into flexor pollicis longus and ...
Mortimer J T - - 1979
A new technique for measuring neuromuscular junction continuity is described. Junctional transmission is evaluated by integration of the electromyographic (EMG) response induced by intramuscular electrical stimulation. The unique characteristics of this monitoring technique are the use of intramuscular stimulation and a varying stimulation rate. The stimulus frequency is made to ...
Schweitzer T W - - 1979
The inspiratory diaphragmatic EMG was recorded via esophageal electrodes in six normal subjects. The EMG and ECG signals were analyzed by power density spectral analysis, before and after band-pass filtering (20--1,600 Hz). The EMG spectrum was concentrated in the bandwidth 25--250 Hz. Electrode motion introduced a significant artifact only at ...
Stull G A - - 1978
The effects of varying fatigue levels on reaction-time components were determined for 20 young, adult males. Each subject squeezed a hand-gripping device until strength decrements of 20, 40, or 60% were recorded; then the subject released his tension and then reacted to an auditory stimulus by gripping as quickly and ...
Prosek R A - - 1978
In this study, six patients who were judged to produce speech with excessive laryngeal tension participated in 14 30-min biofeedback training sessions. The EMG signal, measured by bipolar surface electrodes placed over the cricothyroid region, was amplified, integrated, and used to control the output of a voltage controlled oscillator (VCO) ...
Givens M W - - 1978
Neuromuscular adaptations to a submaximal static contraction for a period of 2 min were investigated using children as subjects to detect changes in the contributing frequency components of the electromyogram (EMG) recorded from surface electrodes. The purpose of this study was to determine the similarity between EMG response patterns of ...
Naliboff B D - - 1978
The relationship between finger pulse amplitude (PA) and frontalis EMG was studied first by looking at general physiological changes accompanying successful bidirectional PA control. Seven successful subjects were then asked to produce two patterns of PA and EMG (PAincEMGdec and PAdecEMGdec) while receiving both PA and frontalis EMG biofeedback. Results ...
Bigland-Ritchie B - - 1978
1. The fatigue of force that occurs during the first 60 s of a maximum voluntary contraction of the human quadriceps has been examined by comparing the voluntary force with that obtained by brief tetanic stimulation at 50 Hz in nine healthy subjects. In three subjects the voluntary force declined ...
Larson C R - - 1978
Eight macaques were trained on one of two isometric force regulation tasks. Six animals were trained to maintain a static force for a 2-sec period, and two animals were trained to make a rapid series of bites on a force transducer four times in succession. Electromyographic (EMG) electrodes were chronically ...
Samans K E - - 1978
An inexpensive electronic device employing a miniaturised infrared reflection detector is described which enables the automatic registration of intrinsic radial contraction activities of protoplasmic strands of Physarum growing on their original substrate. Advantages and shortcoming of the new registration technique are discussed in relation to recent tensiometric techniques applied to ...
Hoyle G - - 1978
The jumping muscle of orthopterous insects contains fibres that possess an intrinsic rhythm (IR) of slow contraction. The contributing fibres are generally synchronized, but as many as three or four pacemakers are present. The frequency, amplitude and duration of IR contractions fluctuate erratically over a 24 h period. Metathoracic DUM ...
Hirose H - - 1978
By means of pellet tracking techniques using an X-ray microbeam system, observations of the articulatory movements of various types of dysarthric subjects were conducted. In selected cases, electromyography (EMG) was also performed. The data were specifically examined for range, velocity, and consistency (reproducibility) of the movements of the articulators, as ...
Gydikov A - - 1978
A new method has been worked out for selective recording of the impulses of individual MU under high muscular efforts. It is suggested to use the EMG derivatives (the differentiated EMG-DEMG and the double differentiated EMG-DDEMG and possibly the higher derivatives). It was demonstrated that at different stationary isometric tensions ...
Viitasalo J H - - 1977
Electromyographic (EMG) activity of m. rectus femoris muscle was registered from young male and female subjects during maintained isometric knee extension at 60% of maximal voluntary contraction. The following EMG parameters were analyzed for the entire fatigue time: integrated EMG (IEMG), averaged motor unit potential (AMUP) and power spectral density ...
Lopata M - - 1977
To determine a reliable quantitative method of measuring diaphragmatic EMG (EMGdi), electrical activity of the diaphragm was obtained via an esophageal electrode during CO2 rebreathing in 6 normal males and processed three different ways: 1) integration (area), 2) as a moving time average, and 3) as a moving time variance. ...
Manns A - - 1977
The relation between mechanical muscular activity (5 - 7.5 - 10 - 15 - 20 Kp of masticatory force) and electrical muscular activity (EMG) was studied during prolonged isometric contractions of the human masseter and temporal muscles, at different degrees of muscular elongation (0.5 - 5 - 10 - 20 ...
Hinghofer-Szalkay H - - 1976
The spontaneous contractions of segments of rat portal veins have been examined in vitro under isotonic and isometric conditions. The power density spectra of recorded time series lasting 10-60 min were calculated. The spectra usually consist of harmonic frequency components. Only during shorter periods of analysis (10 min time series) ...
Greenwood R - - 1976
The electromyographic (EMG) response of soleus to a sudden fall has previously been shown to consist of two peaks of activity, the first a response to release, and the second in relation to landing (Greenwood and Hopkins, 1976). We have now examined activity in soleus during falls at various reduced ...
Viviani P - - 1976
An attempt was made to determine the average stiffness and viscosity of the muscle groups responsible, in human subjects, for the flexion and extension of the forearm, when these movements are produced intentionally. To this end, the subjects were instructed to produce sinusoidal movements by tracking acoustic and visual signals. ...
Hogan N - - 1976
The use of EMG as a proportional control signal for prostheses is reviewed. The lack of success of existing proportional EMG-controlled prostheses is shown to be attributable in the greater part to the presence of low frequency "noise" in the processed EMG signal. If EMG is to yield useful proportional ...
Aaron S L - - 1976
An electromyographically-controlled elbow prosthesis, the "Boston arm", was tested with constant and sinusoidally-modulated inputs under different loading conditions. These tests were used to determine the frequency response of the EMG amplifier, the range of motor speeds, the force-velocity curve, and the frequency response of the prosthesis for cyclic movements. Human ...
Tabatabai M - - 1975
Ureteral motility was studied in 40 subjects with normal urinary tract systems. Although the contraction waves were often monophasic in shape some were characterised by the presence of a notch on the contraction or relaxation limb of the peristaltic complex, indicating that notched complexes do not necessarily signify obstructive uropathy. ...
Milner-Brown H S - - 1975
1. Motor units in the first dorsal interosseus muscle of normal human subjects were recorded by needle electrodes, together with the surface electromyogram (e.m.g.). The wave form contributed by each motor unit to the surface e.m.g. was determined by signal averaging. 2. The peak-to-peak amplitude of the wave form contributed ...
Viitasalo J H - - 1975
Reliability and constancy of recordings of EMG signal characteristics were investigated from the measurements taken with miniature size surface electrodes during submaximal and maximal contraction of the rectus femoris muscle. The following EMG variables were studied: integrated EMG (IEMG) various bandwidths of the power spectral density function, mean power frequency ...
Jones J G - - 1975
The purpose of this study was to determine whether dominant components of the motor potential recorded from the scalp, were coincident with the rise and fall of muscular activity in single movements and return movements in serial flexion and extension of the elbow. Electroencephalographic recordings obtained from two right-handed subjects ...
Rios E - - 1975
(1) The effects of previous contractions on the actual contractile strength is studied in strips of toad ventricle. The inotropic effect is quantified by superposing a conditioning contraction to a rhythm of definite frequency, its measure being the difference in strength between a rhythm contraction in the presence and in ...
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