• Title/Summary/Keyword: Electrical stimulation system

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The development of a high efficient transcranial magnetic stimulation adopted real time-charging-discharging circuit

  • Kim, Whi-Young;Park, Sung-Joon
    • Journal of IKEEE
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    • v.14 no.2
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    • pp.9-15
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    • 2010
  • In this study, we have been proposed the new type of a transcranial magnetic stimulation adopted a variable voltage capacitor with Cockcroft-Walton circuit and constant-frequency current resonant half-bridge inverter. This a transcranial magnetic stimulation has some merits compared with the conventional one. First, it doesn't require the high voltage transformer. And second, it has less switching losses, compact size and capability in adjusting the transcranial magnetic stimulation output energy precisely. In this paper, we have performed the output characteristics of a transcranial magnetic stimulation system which is well known as magnetic stimulation. The tested results are described as a function of pulse repetition rate and switching numbers of the half-bridge inverter.

Effects of Combined Functional Electrical Stimulation and Joint Mobilization on Muscle Activation and Mobility of Ankle Joints and Modified Functional Reach Test in Stroke Patient

  • Kim, Su-Jin;Son, Ho-Hee
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.2
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    • pp.41-51
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    • 2019
  • PURPOSE: This study was conducted to investigate the effects of combined Joint Mobilization and Functional Electrical Stimulation on Muscle Activation and Mobility of ankle joints in stroke patients and their Modified Functional Reach Test (MFRT) results. METHODS: A total of 26 patients with stroke were randomly selected for enrollment in this study. (1) Functional Electrical Stimulation (FES) (2) combined Joint Mobilization and FES. An EMG system was used to measure tibialis anterior and gastrocnemius activities. Range Of Motion (ROM) of Ankle Joint and MFRT for Dynamic Balance. Pre and post intervention results were compared by paired-t-tests and differences in changes after intervention between groups were identified by the independent t-test. RESULTS: The muscle activation, ROM, and MFRT differed significantly in the experimental group (p<.05). The ROM was significantly different for the active dorsiflexion pre and post intervention in the group that received FES alone (p<.05). CONCLUSION: The results of this study suggest use of a systematic program of proactive posture control to prevent dysfunction when planning interventions for ankle joints can help stroke patients walk efficiently.

Effects of Electrical Stimulation on the Mast Cell of Skin in Rats (전기자극이 흰쥐의 피부 비만세포에 미치는 영향)

  • Lee Jae-Hyoung;Jekal Seung-Joo;Park Seung-Teack
    • The Journal of Korean Physical Therapy
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    • v.11 no.3
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    • pp.81-87
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    • 1999
  • The purpose of this study was to determine the effect of electrical stimulation on the number of MCs and percent of degranulated MCs in rat skin. Twelve male Sprague-Dawley rats were divided into two group; electrical stimulation group (n=6) and control group (n=6). Each animals hair on the back was removed. The electrical stimulation group received an positive rectangular pulsed electrical stimulation, while the control group was given the same treatment without electricity. The biopsy specimens were fixed in formalin, embedded in paraffin and stained with toluidine blue-nuclear fast red and alcian blue-safranin O. respectively. The MCs were counted using a light microscope and computerized image analysis system and calculated as the density and the percent. A t-test showed a significantly higher density of MCs in the electrical stimulated rats than control rats(p<0.05), and the percent of degranulated MCs in the electrical stimulated rats was higher than in the control rats (p<0.05) in toluidine blue stained sections. The density of MCs was significantly higher in the electrical stimulated rats than the control rats in alcian blue-safranin O Stained sections (P<0.01). An analysis of variance showed that the densities of CTMCs was significantly lower than the densities of MMCs and mixed MCs in electrical stimulated rat in alcian blue-safranin O Stained sections (p<0.05). These results suggest that the electrical stimulation may have potential for increasing the number of MCs and lead to degranulate the MCs in rat skin.

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식육의 연화증진에 관한 최근의 연구동향 - 적색육의 연도 증진에 이용되는 전기자극의 작용 -

  • 황인호
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2002.05a
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    • pp.17-25
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    • 2002
  • Application of electrical stimulation in the red meat species (eg. beef and sheep) processing has been erratic around the world and this may reflect an incomplete knowledge of how to optimise the technology. Although it is well established that stimulation increases the rate of post-mortem glycolysis other biochemical and biophysical effects have been implicated with the use of this technology. On the basis of currently available knowledge, this mini-review seeks to examine the current theories about the effect of stimulation on post-mortem muscle. The classical view that stimulation prevents muscle from shortening excessively during rigor development has been expanded to include the possibility that it also results in physical disruption of muscle structure. The interaction of these effects with the acceleration of the rate of proteolysis through activation of the calpain protease system has not been comprehensively reviewed in the past. As a result of conclusion driven, this article highlights several areas that may prove fruitful for further research. The challenge for further development of electrical stimulation systems is optimisation of the activation of the enzyme systems in parallel with manipulation of chilling regimes so as to ensure rigor mortis is achieved at temperatures which minimise shortening. The potential of regional stimulation of sections of the carcass to achieve this outcome is worthy of study given the different fibre composition of muscles and temperature gradients.

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Effects of Electrical Stimulation on the Nucleolar Organizer Region in Keratinocyte of Wounded Skin in Rat (전기자극이 흰쥐 창상 표피세포의 핵소체형성부위에 미치는 영향)

  • Lee Jae-Hyoung;Jekal Seung-Joo;Park Seung-Teack
    • The Journal of Korean Physical Therapy
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    • v.12 no.1
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    • pp.1-7
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    • 2000
  • The purpose of this study was to determine the effect of microamperage electrical stimulation on the number of argyrophilic nucleolar organizer region (AgNOR) in rat skin. Twenty four male Sprague-Dawley rats were divided into electrical stimulation and control group. Bach animals hair on the back was removed. The electrical stimulation group received an positive rectangular positive electrical stimulation with $500{\mu}A$, while the control group was given the same treatment without electricity. The rats were sacrificed at 4 and 7 day of stimulation, respectively. The biopsy specimens were fixed in formalin, embedded in paraffin and stained with silver nitrate. The AgNOR were counted using a light microscope and computerized image analysis system and calculated as the mean number of AgNOR per nucleus in the epidermal keratinocyte. In control skin, the mean AgNOR count of epidermal keratinocyte at 4 and 7 day were 1.67 and 1.72, whereas electrical stimulated rat had mean AgNOR counts of 2.0 and 2.14, respectively. A Student's t-test showed a significantly higher mean AgNOR number at 4 ana 7 day in the electrical stimulated rats than control rats (p<0.05). The microamperage electric current stimulation increased the epidermal AgMOR expression in incisional wound skin. These results suggest that the microamperage electrical stimulation may promote migration and proliferative activity of epidermal keratinocyte in surgical wound.

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Power-Efficient Wireless Neural Stimulating System Design for Implantable Medical Devices

  • Lee, Hyung-Min;Ghovanloo, Maysam
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.3
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    • pp.133-140
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    • 2015
  • Neural stimulating implantable medical devices (IMDs) have been widely used to treat neurological diseases or interface with sensory feedback for amputees or patients suffering from severe paralysis. More recent IMDs, such as retinal implants or brain-computer interfaces, demand higher performance to enable sophisticated therapies, while consuming power at higher orders of magnitude to handle more functions on a larger scale at higher rates, which limits the ability to supply the IMDs with primary batteries. Inductive power transmission across the skin is a viable solution to power up an IMD, while it demands high power efficiencies at every power delivery stage for safe and effective stimulation without increasing the surrounding tissue's temperature. This paper reviews various wireless neural stimulating systems and their power management techniques to maximize IMD power efficiency. We also explore both wireless electrical and optical stimulation mechanisms and their power requirements in implantable neural interface applications.

The Effect of Electrical Stimulation on the Changes of Skin Temperature in Normal and Low Back Pain Patients (전기자극이 정상인과 요통환자의 체표면 온도 변화에 미치는 영향)

  • Park, Don-Mork;Lim, Jung-Do
    • Journal of Korean Physical Therapy Science
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    • v.5 no.4
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    • pp.817-830
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    • 1998
  • The purpose of this study is to investigate the relationship between effects of TENS (Transcutaneous Electrical Nerve Stimulation) and IFC(Interferrential Current Therapy) to the change of body surface temperature. Cases are 22 normal persons and 22 patients with low back pain. Digital Infrared Thermal Imaging system was used for the detection of body surface temperature. 50Hz in frequency and 25-35mA in intensity were applied to TENS and IFC, 15 and 10 minutes on each. The results were follows ; 1. TENS and IFC has on effect of decreasing surface temperature, which would be from cardiovascular factors. (P<0.001) 2. The influence of IFC to the body surface temperature is greater than TENS, and it seems to be vasoconstriction of sympathetic activity. 3. There were no significant differences of body surface temperature between the two groups before and after electrical stimulation.

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The Influence of Transcutaneous Electrical Stimulation on Autonomic Function (경피신경전기자극이 자율신경계에 미치는 영향)

  • Kang, Jong-Ho;Kim, Yong-Nam
    • Journal of the Korean Society of Physical Medicine
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    • v.4 no.4
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    • pp.241-247
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    • 2009
  • Purpose:The purpose of this study is to investigate the effect of transcutaneous electrical stimulation on autonomic nervous system using heart rate variability analysis. Methods:31 subjects were evaluated with HRV before and after a single high-frequency TENS for 15minutes treatment. The standard deviation of all the normal RR-interval(SDNN) and lower frequency/high frequency ratio(LF/HF ratio) were recorded with TAS-9. Results:After single TENS treatment, autonomic adaptation as analyzed by SDNN was increased from $42.47\pm12.96$ to $4.43\pm16.76$(p>0.05) and autonomic balance as analyzed by LF/HF ratio was increased from $1.4\pm0.45$ to $1.45\pm0.41$(p>0.05). Conclusion:In this study, SDNN and LF/HF ratio changed in health young students as a result of single TENS treatment. But there is no significant difference between pre-treatment and post-treatment of SDNN and LF/HF ratio.

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Fundamental Characteristics of Isometric Muscle Force Potentiation induced by Surface Stimulation in FES (기능적 표면 전기자극에 의해 유발되는 등척성 근력강화현상의 기초적 특성)

  • 엄광문
    • Journal of Biomedical Engineering Research
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    • v.22 no.2
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    • pp.151-156
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    • 2001
  • A computer model of the musculoskelotal system that provides accurate prediction of muscle force and body movement trom the stimulation input is desired for the effective control system design in FES. This paper aims to investigate the fundamental properties of the gradual muscle force potentiation that was not included in the previous muscle models, for future development of a model that provides vetter prediction of FES-induced muscle force and body movement. Specifically, hou the muscle length was investigated. The experimental results showed that both the force increment ratio and the time-to-peak during electrical stimulation decreased with stimulatino frequency. When the muscle potentiation state was saturated by preceding stimulation. the force did not increase any more during additive stimulation. Muscle length significantly affected the force potentiation in such a way that the force increment ratio decreased with muscle length. A new model of the muscle potentiation based on these results is desired in the future.

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Fully Implantable Deep Brain Stimulation System with Wireless Power Transmission for Long-term Use in Rodent Models of Parkinson's Disease

  • Heo, Man Seung;Moon, Hyun Seok;Kim, Hee Chan;Park, Hyung Woo;Lim, Young Hoon;Paek, Sun Ha
    • Journal of Korean Neurosurgical Society
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    • v.57 no.3
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    • pp.152-158
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    • 2015
  • Objective : The purpose of this study to develop new deep-brain stimulation system for long-term use in animals, in order to develop a variety of neural prostheses. Methods : Our system has two distinguished features, which are the fully implanted system having wearable wireless power transfer and ability to change the parameter of stimulus parameter. It is useful for obtaining a variety of data from a long-term experiment. Results : To validate our system, we performed pre-clinical test in Parkinson's disease-rat models for 4 weeks. Through the in vivo test, we observed the possibility of not only long-term implantation and stability, but also free movement of animals. We confirmed that the electrical stimulation neither caused any side effect nor damaged the electrodes. Conclusion : We proved possibility of our system to conduct the long-term pre-clinical test in variety of parameter, which is available for development of neural prostheses.