• Title/Summary/Keyword: Plasma Space

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Cytochemistry of cellulase in Capitate Glandular Trichomes of Pelargonium ${\times}$ fragrans (Geraniaceae)

  • Nam, Ko-Kyung;Lee, Kyung-Whan;Lee, Sang-Eun;Kim, Eun-Soo
    • 한국전자현미경학회:학술대회논문집
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    • 2007.05a
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    • pp.75-78
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    • 2007
  • The localization of cellulase were investigated in the capitate glandular trichomes of Pelargonium ${\times}$ fragransby a transmission electron microscopy. The secretory cells of capitate trichomes involved in biosynthesis and its secretion. Secretory material is transported to the space between the plasma membrane and cell wall, and subsequently accumulated in the secretory cavity. The splitting of secretory cell wall during the formation of secretory cavity is suggested that wall-forming enzymes, such as cellulase, may contribute to the wall separation process. Cellulase reaction product was localized in the secretory cell, the secretory cavity and in the subcuticular wall of glandular trichomes. Reaction products were present over fibrillar matrix in the secretory cavity associated with both the inner wall and the subcuticular wall.

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Discharge Characteristics of a KSTAR NBI Ion Source

  • Chang Doo-Hee;Oh Byung-Hoon
    • Nuclear Engineering and Technology
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    • v.35 no.3
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    • pp.226-233
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    • 2003
  • The discharge characteristics of a prototype ion source was investigated, which was developed and upgraded for the NBI (Neutral Beam Injection) heating system of KSTAR (Korea Superconducting Tokamak Advanced Research). The ion source was designed for the arc discharge of magnetic bucket chamber with multi-pole cusp fields. The ion source was discharged by the emission-limited mode with the control of filament heating voltage. The maximum ion density was 4 times larger than the previous discharge controlled by a space-charge-limited mode with fully heated filament. The plasma (ion) density and arc current were proportional to the filament voltage, but the discharge efficiency was inversely proportional to the operating pressure of hydrogen gas. The maximum ion density and arc current were obtained with constant arc voltage ($80{\sim}100V$), as $8{\times}10^{11}cm^{-3}$ and 1200 A, respectively. The estimated maximum beam current was about 35 A, extracted by the accelerating voltage of 80kV.

Brain Uptake and the Analgesic Effect of Oxytocin - its Usefulness as an Analgesic Agent

  • Kang, Young-Sook;Park, Ji-Hyun
    • Archives of Pharmacal Research
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    • v.23 no.4
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    • pp.391-395
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    • 2000
  • To establish the usefulness of oxytocin (OT) as an analgesic for women in delivery, the pharmacokinetic parameters and blood-brain barrier (BBB) permeability of [$^3H$] OT were obtained using an intravenous injection technique or the internal carotid artery perfusion/capillary depletion (ICAP/CDM) method. Brain uptake of OT was similar to that of sucrose, plasma space marker, indicating that OT has a poor BBB permeability. Moreover, the analgesic effects of OT injected through the jugular vein on nociception were evaluated by the tail-flick method. The antinociceptive effects of OT injected at a dose of 0.2 ${m}g/kg$or 2 ${m}g/kg$ were dose-dependent. In addition, the analgesic effects of OT on the CNS were unaffected by naloxone, a m-receptor antagonist. In a similar manner to the opioid system, OT may play a modulatory role in antinociception.

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A Study on the Radiative Heat Transfer Characteristics in the Fluidized Particles Layer (유동입자층에서의 복사열전달 특성에 관한 연구)

  • 김금무;김용모;김경근
    • Journal of Advanced Marine Engineering and Technology
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    • v.18 no.4
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    • pp.33-42
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    • 1994
  • The radiative heat transfer analysis in the fluidized particles layer has important application in many technological areas such as combustion chambers at high pressure and temperature, plasma generators for nuclear fusion, MHD generator using pulverized coal and the liquid droplet radiator used to reject wasted heat from a power plant operating in space. To accurately model the radiation properties of the fluidized particles layer, it is necessary to know the radiation interchange factors of particles in each layer. But the solutions are usually not possible for the equations of radiative heat transfer because it has an inherent difficulty in treating the governing intergo- differential equations, which are derived from the remote effects of radiative heat transfer. In this study, the analysis uses the Monte Carlo simulation method with optical depth model to calculate the radiation interchange factors of particles in each layer with wall and with each other.

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An Automated System for Empirical Forecasting of Solar Flares and CMEs

  • Park, Sung-Hong;Yamamoto, Tetsuya
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.129.2-129.2
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    • 2012
  • Solar flares and coronal mass ejections (CMEs) are two major solar eruptive phenomena which can cause enormous economic and commercial losses: (1) flares are sudden, rapid, and intense brightenings from radio waves to Gamma-rays in the chromosphere and corona, and (2) CMEs are large-scale transient eruptions of magnetized plasma from the solar corona that propagate outward into interplanetary space. Most flares and CMEs occur in magnetically complicated solar active regions (ARs). Therefore, it is crucial to investigate magnetic fields in ARs and their temporal variations for understanding a precondition and a trigger mechanism related to flare/CME initiation. In this presentation, we will introduce an automated system for empirical forecasting of flares and CMEs in ARs using full-disk photospheric line-of-sight magnetogram data taken by the Helioseismic and Magnetic Imager (HMI) onboard the SDO.

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A Study on the Space Charge Effect of Display Discharge for Plasma Display Pane (플라즈마 디스플레이 패널의 표시방전에 미치는 공간전하의 영향에 관한 연구)

  • Son, Duk-Won;Ryeom, Jeong-Duk
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.35-38
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    • 2005
  • Full-HDTV급 PDP를 구현하기 위해서는 고속 어드레스 구동이 필요하며 이러한 기술은 AWD 구동방식으로 구현하는 것이 용이하다. AWD 구동방식은 하나의 sustain 펄스 휴지기안에 복수개의 scan 펄스를 설치하는 것이 바람직하며 이 경우 sustain 펄스와 sustain 펄스 사이가 넓어진다. 본 연구에서는 이 휴지기를 고려한 sustain 방전특성을 해석하였다. 실험결과 address 바로 다음에 나오는 첫 번째 sustain 펄스는 공간전하 의존도가 높으며 두 번째 펄스부터는 공간전하 의존도보다는 벽전하 의존도가 더 높다는 사실을 알았다. 또한 수십${\mu}s$를 가지는 휴지기간에도 균일한 sustain 동작마진을 얻을 수 있음을 알았다.

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Kinetic Studies of Parent Compounds and Its Metabolite by Combined Treatment of Allyl Alcohol with Ethanol in vivo (Allyl Alcohol 및 Ethanol 혼합투여에 의한 혈중 농도 변화 및 독성과의 상관성)

  • 이주영;정승민;이무열;정진호
    • Toxicological Research
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    • v.14 no.4
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    • pp.557-562
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    • 1998
  • Allyl alcohol is metabolized in the liver through two steps, first to reactive acrolein by alcohol dehydrogenase (ADH), subsequently to acrylic acid by aldehyde dehydrogenase (ALDH). Since ethanol could compete the same enzymes to be metabolized in the liver, we have determined the plasma concentrations of allyl alcohol and ethanol followed by combined treatment. Pretreatment of rats with 2g/kg ethanol followed by ip administration of 40mg/kg allyl alcohol increased the lethality significantly. Determination of in vivo blood concentrations revealed that ethanol pretreatment caused the apparent decrease in allyl alcohol clearance, whereas acetaldehyde level in blood increased significantly by allyl alcohol treatment, as determined by head space GC analysis. Treatment of 4-methylpyrazole, an inhibitor of ADH, delayed allyl alcohol elimination significantly and reduced its lethality. Collectively, these findings suggested that reduction of allyl alcohol clearance in the presence oj ethanol was mediated through ADH competitive inhibition.

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ORIGINS OF THE FLOW AND MAGNETIC STRUCTURE INVOLVED IN THE FORMATION AND ERUPTION OF A SOLAR PROMINENCE

  • Magara, Tetsuya
    • Journal of The Korean Astronomical Society
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    • v.54 no.5
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    • pp.157-170
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    • 2021
  • We investigate flow and magnetic structure of a solar prominence with a focus on how the magnetic field originally determined by subsurface dynamics gives rise to the structure. We perform a magnetohydrodynamic simulation that reproduces the self-consistent evolution of a flow and the magnetic field passing freely through the solar surface. By analyzing Lagrangian displacements of magnetized plasma elements, we demonstrate the flow structure that is naturally incorporated to the magnetic structure of the prominence formed via dynamic interaction between the flow and the magnetic field. Our results explain a diverging flow on a U-loop, a counterclockwise downdraft along a rotating field line, acceleration and deceleration of a downflow along an S-loop, and partial emergence of a W-loop, which may play key roles in determining structural properties of the prominence.

Observation of the Rebound Shock Waves and the EUV Brightening of a Light Bridge Jet

  • Yang, Heesu
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.44.1-44.1
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    • 2020
  • Hα jets of cool chromospheric plasma are protruding into the solar corona 10-100 Mm above the photosphere. The driving mechanisms of Hα jets have been widely studied for decades. However, the detailed process is still elusive. We observed shock signatures moving along a dark jet using 1.6 meter Goode Solar Telescope at Big Bear Solar Observatory. The first shock front of the jet shows sharp --- when it moves upward, while fuzzy and granulated when it moves downward. The jet itself extends upward when the second shock front of the jet reaches the top of the jet. We find abrupt EUV brightenings when the second shock front collides with the edge of the jet. The third front and the fouth front quasi-periodically. These phenomena might be the signs of the rebound shock waves triggered by p-mode wave leakages at the bottom of the jets. Our observation suggests that the jet can be triggered by the rebound shock waves generated by the p-mode waves leaked at the bottom of the jets.

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Simple modeling to explore temperatures, heated temperature, and Kappa values of a current sheet observation

  • Lee, Jin-Yi;Raymond, John C.;Reeves, Katharine K.;Shen, Chengcai;Kahler, Stephen;Moon, Yong-Jae;Kim, Yeon-Han
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.79.2-79.2
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    • 2021
  • We explore the range of possibilities of temperatures, heated temperature, and Kappa values of a current sheet observation on 2017 September 10. First, we construct a grid model with rapid heating (Theat) and various Kappa (κ) values. We assume a simple density model and use adiabatic cooling to set the temperature during expansion. Next, we calculate the ion fractions using a time-dependent ionization model with adiabatic cooling and various Kappa values. The calculated ion fractions are used to simulate the DNs of the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory. Then, we explore the possible range of the temperatures and Kappa values, comparing the simulated images with the observations. Finally, we discuss the range of the heated temperature and Kappa values and whether the result of this study suggests continuous heating of the current sheet plasma during the expansion.

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