• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.787-791
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• 2004

We investigated field-effect ion-transport devices based on carbon nanotubes by using classical molecular dynamics simulations under applied external force fields, and we present model schematics that car be applied to the nanoscale data storage devices and unipolar ionic field-effect transistors. As the applied external force field is increased, potassium ions rapidly flow through the nanochannel. Under low external force fields, ther nal fluctuations of the nanochannels affect tunneling of the potassium ions whereas the effects of thermal fluctuations are negligible under high external force fields. Since the electric current conductivity increases when potassium ions are inserted into fullerenes or carbon nanotubes, the field effect due to the gate, which can modify the position of the potassium ions, changes the tunneling current between the drain and the source.

• BMB Reports
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• v.48 no.12
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• pp.677-684
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• 2015

Cardiovascular function is regulated by the rhythmicity of circadian, infradian and ultradian clocks. Specific time scales of different cell types drive their functions: circadian gene regulation at hours scale, activation-inactivation cycles of ion channels at millisecond scales, the heart's beating rate at hundreds of millisecond scales, and low frequency autonomic signaling at cycles of tens of seconds. Heart rate and rhythm are modulated by a hierarchical clock system: autonomic signaling from the brain releases neurotransmitters from the vagus and sympathetic nerves to the heart's pacemaker cells and activate receptors on the cell. These receptors activating ultradian clock functions embedded within pacemaker cells include sarcoplasmic reticulum rhythmic spontaneous Ca²⁺ cycling, rhythmic ion channel current activation and inactivation, and rhythmic oscillatory mitochondria ATP production. Here we summarize the evidence that intrinsic pacemaker cell mechanisms are the end effector of the hierarchical brain-heart circadian clock system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.741-744
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• 2001

This paper described on the fabrication of microstructures by DRIE(Deep Reactive Ion Etching). SOI(Si-on-insulator) electric devices with buried cavities are fabricated by SDB technology and electrochemical etch-stop. The cavity was fabricated the upper handling wafer by Si anisotropic etch technique. SDB process was performed to seal the fabricated cavity under vacuum condition at -760 mm Hg. In the SDB process, captured air and moisture inside of the cavities were removed by making channels towards outside. After annealing(1000$^{\circ}C$, 60 min.), the SDB SOI structure was thinned by electrochemical etch-stop. Finally, it was fabricated microstructures by DRIE as well as a accurate thickness control and a good flatness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.739-742
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• 2002

This paper described on the fabrication of microstructures by DRIE(deep reactive ion etching). SOI(Si-on-insulator) electric devices with buried cavities are fabricated by SDB technology and electrochemical etch-stop. The cavity was fabricated the upper handling wafer by Si anisotropic etch technique. SDB process was performed to seal the fabricated cavity under vacuum condition at -760 mmHg. In the SDB process, captured air and moisture inside of the cavities were removed by making channels towards outside. After annealing($1000^{\circ}C$, 60 min.), The SDB SOI structure was thinned by electrochemical etch-stop. Finally, it was fabricated microstructures by DRIE as well as an accurate thickness control and a good flatness.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.20-27
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• 2002

A role for ATP in nociception and pain induction was proposed. ATP-gated P2X ion channel receptors are localized throughout the nervous system and have been identified on neurons which participate in conduction of nociceptive information from the periphery to central nervous system. We consider the role of ATP as a peripheral activator of nociceptive sensory neuron via ATP-gated ion channels.

• The Korean Journal of Ecology
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• v.20 no.2
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• pp.83-94
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• 1997

Stomatal closing by ozone and water stress could reduce further ozone injury by inhibition of ozone influx to the tissue. Direct effect of ozone on stomata can be explained from two aspects which are a stimulation of stomatal closing and an inhibition of stomatal opening. An increase of $Ca^{2+}$ influx into cytoplasm by ozone could stimulate potassium efflux ion channel and inhibits inward potassium ion channels. By this mechanism ozone could induce stomatal closing. On the other hand, ozone could inhibit stomatal opening by affecting the activity of $H^{+}$ dependent ATPase of the membrane in guard cells. This would inhibit proton efflux which precede stomatal opening. It is also possible that ozone could reduce the activity of photosynthesis in guard cells which lead to affect the production of osmotically active sugars and energy. Indirect effect of ozone to stomata is through the effect of $CO_2$ elevation as a result of damage of the photozynthetic machinery. This indirect effect is slower than the direct effect.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.230-230
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• 2004

Polyamines, namely putrescine, spermidine, and spermine, are biogenic low-molecular-weight aliphatic amines. Polyamines play important roles in DNA stabilization, RNA and protein synthesis, membrane stabilization, modulation of ion channels, and protection against oxygen radicals and are essential for cell homeostasis, cell growth, and tumorigenesis. (omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.39-39
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• 2002

Microglia are known to have an important function as brain macrophage during immunological processes, oncogenesis, and regeneration in the central nervous system (CNS). A wide variety of ion channels have been identified and characterized in microglia including inward rectifier $K^{＋}$ channel (Kir), voltage dependent $K^{＋}$ channel (Kv), $Ca^{2＋}$-release activated $Ca^{2＋}$ channel (CRAC).(omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.22-23
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• 1999

Voltage-gated $K^{＋}$ channels represent the most complex group of ion channel genes expressed in cardiovascular system. The human Kv1.5 channel (hKv1.5) represents the $I_{Kur}$ repolarizing current in atrial myocytes. The hKv1.5 channel is functionally modulated by the Kv$\beta$1.3 subunit, which converts it from a delayed rectifier to a channel with rapid inactivation and enhanced voltage sensitivity.(omitted)d)

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.25-25
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• 1997

Cyclic nucleotide-gated channels (CNGC's) contain a putative N-glycosylation site (Asn-X-Ser/Thr) in the linker regions connecting the fourth transmembrane domain (S4) and the ion conduction pore (P-region). This putative N-glycosylation site is highly conserved and thus found in many different CNGC in various organisms, from fruit to human.(omitted)