• 대한약리학회지
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• 제19권2호
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• pp.1-8
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• 1983

Prostaglandin(PG) is ubiquitously distributed in most mammalian tissue and their actions are complicated. Especially in autonomic nervous system, there are evidences indicating that PGs act as neuromodulators i.e., PGs, which are released in the vicinity of autonomic neuroeffector junctions, influence the release and the response of the neurotransmitter. Present study was undertaken to elucidate the interrelationship between $PGF_{2\alpha}$ and adrenergic ${\alpha}_2-receptor$ function in electrical field stimulation induced contractile response of vas deferens in rat. Male rat, weighing 150{\sim}200\;g, was sacrificed and vas deferens was obtained. The isolated vas deferens strip was placed between two platinum electrodes in temperature controlled $(37^{\circ}C)$ muscle chamber containing Tyrode's solution and the electrical field stimulation(EFS) induced contraction was recorded with Grass Polygraph(Model 7) via force displacement transducer (FT .03, Grass). The results are summarized as follows: 1) Electrical field stimulation for 1sec( 1 msec, 40 cps) induced contraction of vas deferens was completely blocked by tetrodotoxin. 2) Bretylium caused marked inhibition of the EFS-induced contraction, hut tyramine and cocaine augmented the contraction. 3) EFS-induced contraction was inhibited or little affected in distal portion of vas deferens by norepinephrine or methoxamine, but the contraction was rather augmented by the ${\alpha}-agonists$ in proximal portion. 4) Clonidine inhibited the EFS-induced contraction proportionally to the concentration in distal portion, which was blocked by yohimbine pretreatment, but in the presence of $PGF_{2\alpha}$ the blockade by yohimbine was reversed. 5) Indomethacin pretreatment reduced the effect of clonidine, but addition of $PGF_{2\alpha}$ after washing-out the indomethacin caused the contraction to the control level. From these results it is suggested that PG synthesis is a necessary step and the PG itself has a permissive role in ${\alpha}_2-adrenoceptor$ action in rat vas deferens.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권12호
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• pp.708-716
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• 2003

The surface EMG signal detected from voluntarily activated muscles can be used as a control signal for functional electrical stimulation. To use the voluntary EMG signal, it is necessary to eliminate the muscle response evoked by the electrical stimulation and enable to process the algorithm in real time. In this paper, we propose the Gram-Schmidt(GS) algorithm and implement it in FPGA(field programmable gate array). GS algorithm is efficient to eliminate periodic signals like muscle response, and is more stable and suitable to FPGA implementations than the conventional least-square approach, due to the systolic array structure.

• The Korean Journal of Physiology
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• 제23권2호
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• pp.409-420
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• 1989

Extracellular recordings were made from the spinal neurons in the lumbar enlargement of 16 cats before and during electrical stimulation of the radial nerve ipsilaterally and contralaterally. Only neurons activated by remote nerve stimulation (RNS) were included in sample. All the cell classes of spinal neurons which received afferents message from the skin and/or muscles were activated by RNS except LT cells. Approximately three quaters of cells activated by RNS had an inhibitory receptive field (RF) on the ipsilateral hindlimb and two thirds of RNS-activated neurons showed spontaneous activity. The most of these RNS-activated cells seemed to be in deep dorsal horn and in ventral horn as well. Stimulation of contralateral radial nerve produced activation of spinal neurons almost same degree as by ipsilateral nerve stimulation. The optimal stimulation parameters of radial nerve for activation of spinal cells were 5Hz-0.5 msec-2V while threshold stimulus for activation was approximately 0.18 V. Following close intra-arterial injection of $K^+$ ion excitability of RNS-activated neuron was increased in 4 of 8 cells whereas it was decreased in 2 of 8 cells. The results indicate that there are some spinal neurons in the lumbar enlargement of cats that can be activated by forelimb afferent $(A{\beta}\;&\;A{\delta})$ inputs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.73-76
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• 1998

We give pressure stimulation into organic thin films and detect the induced displacement current. then manufacture a device under the accumulation condition that the state surface pressure is 15[mN/m]. In processing of a device manufacture. We can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/organic thin films(polyimide)/Au, the number of accumulated layers are 31,35, and 41. I-V characteristic of the device is measured from 0[V] to +5[V]. The maximum value of measured current is increased as the number of accumulated layers are decreased. The resistance for the number of accumulated layers, the energy density for an input voltage show desired results, and the insulation of a thin film is better as the interval between electrodes is larger.

• 대한의용생체공학회:의공학회지
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• 제32권4호
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• pp.305-311
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• 2011

For effective stimulation with tDCS, spatial focality of induced electrical field(EF) and current density(CD) is one of the important factors to be considered. Recently, there have been some studies to improve the spatial focality via different types of electrodes and their new configurations: some improvements using ring electrodes were reported over the conventional pad electrodes. However, most of these studies assumed isotropic conductivities in the head. In this work, we have investigated the effect of tissue anisotropy on the spatial focality of tDCS with the 4 + 1 ring electrode configuration via a 3-D high-resolution finite element(FE) head model with anisotropic conductivities in the skull and white matter. By examining the profiles of the induced EF from the head models with isotropic and anisotropic conductivities respectively, we found that the spatial focality of the induced EF significantly drops and get diffused due to tissue anisotropy. Our analysis suggests that it is critical to incorporate tissue anisotropy in the effective stimulation of the brain via tDCS.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권8호
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• pp.397-400
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• 2006

An optimized iron core structure of stimulating coil are presented in order to control the induced electric field distribution using the Continuum Design Sensitivity Analysis (CDSA) combined with a commercially available generalized finite element code (OPERA). The results show that a Figure-Of-Eight (FOE) coil as well as a circular coil with the proposed iron core structure can increase induced electric field intensity by more than two times and make better field localization, compared with those of existing stimulation coil with a air core. After considering manufacturing constraints, a practical iron core structure based on the proposed optimized one is proposed and its performance is analyzed.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.75.1-75.1
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• 2003

Low-frequency electrical field stimulation of transmural nerves of cat esophageal circular smooth muscle produces an “off contraction”, which occurs after electirical field stimulation (EFS) of transmural nerves is stopped. We previously examined signal transduction pathways mediating ACh-induced contraction of circular smooth muscle of esophagus. The extracellular Ca$\^$2+/ is needed for the contraction, results in the activation PKC. EFS-induced contraction was abolished by the pretreatments of tetrodotoxin(1 ${\mu}$M) and atropine (1 ${\mu}$M). (omitted)

• 농업과학연구
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• 제40권1호
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• pp.13-18
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• 2013

Effect of electric pulse stimulation was tested on the fruit body formation of valuable mushroom Tricholoma matsutake in the field of natural habitat of this mushroom. After applying the electric stimulator to the specific area of pine forest we found that the treatment especially stimulated the fructification of T. matsutake. And the most valuable findings of our study was that only our treatment plots showed fruit body formation whereas the control plots and the whole natural habitats of our study area showed zero production of this mushroom during the same time. From the point of view of mushroom production, our experiment shows that fruit body production can be upgraded by using pulsed power as an electrical stimulation in the field of the natural habitat of this mushroom. These findings from our experiment confirm the effectiveness of the significance of pulsed power technology for the improvement of T. matsutake fruit body production in the natural habit of this mushroom.

• The Korean Journal of Physiology and Pharmacology
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• 제15권6호
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• pp.415-422
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• 2011

Previously, we reported that besides retinal ganglion cell (RGC) spike, there is ~10 Hz oscillatory rhythmic activity in local field potential (LFP) in retinal degeneration model, rd1 mice. The more recently identified rd10 mice have a later onset and slower rate of photoreceptor degeneration than the rd1 mice, providing more therapeutic potential. In this study, before adapting rd10 mice as a new animal model for our electrical stimulation study, we investigated electrical characteristics of rd10 mice. From the raw waveform of recording using $8{\times}8$ microelectrode array (MEA) from in vitro-whole mount retina, RGC spikes and LFP were isolated by using different filter setting. Fourier transform was performed for detection of frequency of bursting RGC spikes and oscillatory field potential (OFP). In rd1 mice, ~10 Hz rhythmic burst of spontaneous RGC spikes is always phase-locked with the OFP and this phase-locking property is preserved regardless of postnatal ages. However, in rd10 mice, there is a strong phase-locking tendency between the spectral peak of bursting RGC spikes (~5 Hz) and the first peak of OFP (~5 Hz) across different age groups. But this phase-locking property is not robust as in rd1 retina, but maintains for a few seconds. Since rd1 and rd10 retina show phase-locking property at different frequency (~10 Hz vs. ~5 Hz), we expect different response patterns to electrical stimulus between rd1 and rd10 retina. Therefore, to extract optimal stimulation parameters in rd10 retina, first we might define selection criteria for responding rd10 ganglion cells to electrical stimulus.

• 대한치과보철학회지
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• 제34권3호
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• pp.431-437
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• 1996

To evaluate the clinical usefulness of TENS theory, 12 dental studensts of KyungPook National University and 18 prosthodontic patients were applied by 3M DENTAL ELECTRONIC ANESTHESIA and the follwing results were obtained: 1. Using the TENS theory to 12students, and EPT test was conducted and 6 students among total 12 students showed the anesthetic effects to the pain(p<0.05). 2. 15 prosthetically preparated patients show the anesthetic effects to the pain among total 18 patients.