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The Manufacturing of Textile Products with Incorporated Electrodes

Curteza A., Cretu V., Macovei L., Poboroniuc M.

Autex Research Journal

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2016

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Vol. 16, no. 1

13--18

EN

One of the main causes of disabling deficits is neurological affections. Many times, the evolution of the condition leads to a diminution of the patient’s life quality. Functional electrical stimulation (FES) is part of the neurological rehabilitation process that comprises all the actions one can take in order to increase a patient’s integration and autonomy degree from a social and financial point of view. FES is a method based on substituting the commands that are usually transmitted by the nervous system with an electric impulse. The use of such a method on different body areas required the development of some adequate devices, starting with the stimulator itself and finishing with the way in which the stimulus is conveyed to the effectors. Textile materials that incorporate sensors and, mainly, the clothing products that have such components in their structure, have a high applicability potential; they can be used for preventing illnesses and for the rehabilitation of seniors, of people who are confined to bed, sportsmen, people who suffer from long-term illnesses, disabled people, thus diminishing the time one spends in the hospital. A possible solution for manufacturing incorporated textile electrodes consists in the insertion of some electro-conductive yarns onto textile surfaces by using a variety of technologies. The project approaches the use of knitting, a widespread textile technology. The incorporated knitted electrodes were accomplished by applying the knitting technology on single circular small diameter machines. Thus, we were able to obtain a variety of knitted articles as two-dimensional or three-dimensional tubular knitted fabric. Their dimensions, structures, and parameters correspond to the typo-dimensions of the human body and to the purpose for which the clothing product was designed. The knitted versions were tested by using a Microstim2v2 (PW = 300 μs, 40 Hz) neurostimulator for which the current intensity was adjusted to approx. 30 mA.

2

The relationship between changes in joint kinematics parameters and mechanomyographic signals during non-isometric contraction in human skeletal muscle

Ohta Y.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 2

97--104

EN

The present study determines the effects of summation of contraction on joint kinematics in human ankle and mechanomyography (MMG) signals during non-isometric contraction. The excursion and angular velocity of dorsiflexion and eversion were measured during several summation profiles during non-isometric contractions. The joint kinematics parameters and MMG responses to 1–8 pulses at a constant interval of 10 ms were recorded to investigate the effects of different numbers of stimuli. In an examination of two-pulse trains with different inter-pulse intervals, the joint kinematics parameters and MMG responses to inter-pulse intervals of 10–100 ms were recorded from the tibialis anterior muscle. The main finding was that facilitating effects of subsequent stimulation were limited to angular velocity of eversion during the contribution of a second stimulus, suggesting that facilitating effects of second stimulus reflect angular velocity but not joint angle excursion. A comparison with MMG signals clarified that MMG signals poorly correlate with changes in the joint kinematics parameters (excursion and angular velocity) when the inter-pulse intervals or numbers of stimuli are increased. These findings will provide useful information for assessing the muscle contractile properties with evoked MMG signals during non-isometric contraction.

3

Some challenging feedback-control applications in biomedical systems

Ionescu C., Keyser R. de

Journal of Medical Informatics & Technologies

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2005

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Vol. 9

35--46

EN

Natural biological control involves the normal functioning of the living organism (i.e. human body) to regulate its parameters such that the vital functions are kept within the normal operating range. When this natural control fails, the biological feedback (thus a closed loop system) is unstable and/or operates under non-optimal conditions of the vital capacity of the subject. In this context, ensuring surviving capacity of the subject implies to artificially control the vital functions presenting the functional failure. Nowadays technology enables development of artificial closed loop devices to correct and provide the normal functions of the organism, replacing thus the damaged/non-optimal parts or helping in recovering their natural properties (rehabilitation techniques). Two of the most en-vogue applications of artificial control will exemplify the importance and the posed challenges: - a neuroprothesis device to control paralyzed skeletal muscles; this enables rehabilitation of drop-foot or hand-grasp movements with paretic or paralyzed skeletal muscles by use of a self-adaptive (auto-tuning) control strategy; - and an artificial pancreas for diabetes type I patients; the blood glucose control in diabetic patients type I is made by use of an in-house developed model-based predictive control algorithm in which input (insulin rate) and output (glucose level) are constrained.

4

Muscle atrophy after human spinal cord injury

Thomas C. K., Grumbles R. M.

Biocybernetics and Biomedical Engineering

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2005

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Vol. 25, no. 3

39-46

EN

The atrophy that accompanies muscle paralysis cannot always be accounted for by altered muscle use. Muscles innervated from spinal segments near a spinal cord injury also undergo denervation due to death of motoneurons. Intrinsic hand muscles are particularly vulnerable to complete denervation after human cervical spinal cord injury. Early intervention is needed to prevent muscle degeneration following denervation. Neuron replacement is one strategy to restore innervation to denervated muscles and to rescue muscle. Even if the muscles are not under voluntary control, reinnervated muscles can be activated electrically to generate simple functional behaviors.