• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1066-1068
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• 1999

Magnetic field is commonly used in low temperature processing plasmas in order to obtain high density. E $\times$ B magnetron or surface multipole configuration were most popular. However, the properties of capacitively coupled rf plasma confined by axially applied static magnetic fields have rarely been studied. In this paper, the effects of magnetic field on the characteristics of 13.56MHz/40KHz argon plasma will be reported. Ion saturation current, electron temperature and plasma potential were measured by Langmuir probe and omissive probe. At low pressure region ($\sim$10mTorr), ion current was increased by a factor of 3 - 4 due to reduction of diffusion loss of charged particles to the wall. It was observed that magnetic field induces large time variation of the plasma potential. The experimental result was compared with particle-in-cell simulation. It was also observed that electron temperature tend to decrease with increasing magnetic induction level for 40KHz discharge.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.523-527
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• 2012

Silicon carbide (SiC) has recently drawn an enormous amount of industrial interest due to its useful mechanical properties, such as its thermal resistance, abrasion resistance and thermal conductivity at high temperatures. In this study, RF thermal plasma (PL-35 Induction Plasma, Tekna CO., Canada) was utilized for the synthesis of high-purity SiC powder from an organic precursor (hexamethyldisilazane, vinyltrimethoxysilane). It was found that the SiC powders obtained by the RF thermal plasma treatment included free carbon and amorphous silica ($SiO_2$). The SiC powders were further purified by a thermal treatment and a HF treatment, resulting in high-purity SiC nano-powder. The particle diameter of the synthesized SiC powder was less than 30 nm. Detailed properties of the microstructure, phase composition, and free carbon content were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), a thermogravimetric (TG) analysis, according to the and Brunauer-Emmett-Teller (BET) specific surface area from N2 isotherms at 77 K.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.61-64
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• 2004

Recently, the RF inductive discharge or inductively coupled plasma (ICP) continues to attract growing attention as an effective plasma source in many industrial applications, the best known of which are plasma processing and lighting technology. To the point of lighting sources, the electrodeless fluorescent lamps utilizing an inductively coupled plasma (ICP) have been objects of interest and research during the last decades, mainly because of their potential for extremely long life, high lamp efficacies, rapid power switching response. The electrodeless fluorescent lamp that is dealt with in this work comprises a bulb filled with rare gas and amalgam of vaporizable metal and has a coil provided with a winding around the ferrite. Current through a coil produces a magnetic field in the discharge space. The changing magnetic flux then produces an azimuthal electric field E around the coil, according to Faraday's laws of magnetic induction.

• Journal of Microbiology
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• v.34 no.3
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• pp.220-224
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• 1996

Ultrastructural organization of encysting zoospores of Allomyces macrogynus was examined using the methods of cryofixation and freeze substitution. During enxcystment, obvious changes were observed at the surface of the plasma membrane and in the structure of gamma particles. Many multivesicular bodies associated with the plasma membrane were observed at early stages of encystment. After induction of encystment, vesicles were found within the gamma particles. These vesicles appeared to leave gamma particles after forming multivesicular bodies. This study suggests that the cell wall formation during encystment is mediated by the fusion of multivesicular bodies with the plasma membrane.

• Proceedings of the KIEE Conference
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• 2002.06a
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• pp.75-78
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• 2002

In this paper, we investigated the change of wettability, surface potential decay and surface resistivity caused by thermal-treated and plasma-treated FRP respectively for finding out the influence of electrical characteristics on the surface of polymer composites. For the change of wettability, the contact angle of thermal-treated specimen with the high temperature of 200$^{\circ}C$ increased. But that of plasma-treated specimen decreased. The characteristic of surface potential decay shows the tendency of the remarkable decrease on plasma-treated specimens, but no difference on thermal-treated specimen compared with untreated one. Also, for the surface resistivity, it shows the same trend compared with the change of contact angle. We can conclude that the degradation phenomena of epoxy surface are dominated by the induction of hydrophilicity and hydrophobicity.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.4
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• pp.415-424
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• 2016

Berberine is an isoquinoline alkaloid found in Rhizoma coptidis, and elicits anti-inflammatory effects through diverse mechanisms. Based on previous reports that activating transcription factor-3 (ATF-3) acts as a negative regulator of LPS signaling, the authors investigated the possible involvement of ATF-3 in the anti-inflammatory effects of berberine. It was found berberine concentration-dependently induced the expressions of ATF-3 at the mRNA and protein levels and concomitantly suppressed the LPS-induced productions of proinflammatory cytokines ($TNF-{\alpha}$, IL-6, and $IL-1{\beta}$). In addition, ATF-3 knockdown abolished the inhibitory effects of berberine on LPS-induced proinflammatory cytokine production, and prevented the berberine-induced suppression of MAPK phosphorylation, but had little effect on AMPK phosphorylation. On the other hand, the effects of berberine, that is, ATF-3 induction, proinflammatory cytokine inhibition, and MAPK inactivation, were prevented by AMPK knockdown, suggesting ATF-3 induction occurs downstream of AMPK activation. The in vivo administration of berberine to mice with LPS-induced endotoxemia increased ATF-3 expression and AMPK phosphorylation in spleen and lung tissues, and concomitantly reduced the plasma and tissue levels of proinflammatory cytokines. These results suggest berberine has an anti-inflammatory effect on macrophages and that this effect is attributable, at least in part, to pathways involving AMPK activation and ATF-3 induction.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3977-3980
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• 2015

Background: To investigate the effects of preemptive analgesia with parecoxib sodium on haemodynamics and plasma stress hormones in surgical patients with thyroid carcinoma. Materials and Methods: Fifty-seven patients with thyroid carcinoma who underwent thyroidectomy selectively in Laiwu Hospital Affiliated to Taishan Medical University and Binzhou People's Hospital were selected and randomly divided into three groups, 19 cases in each group. The control group was intravenously injected 0.9% sodium chloride injection before anesthesia induction; trial group I was intravenously injected with parecoxib sodium 20 min before anesthesia induction; based on trial group I, trial group II was injected with parecoxib sodium again 12 h after surgery. The levels of plasma norepinephrine (NE), cortisol (Cor) and blood glucose before, 12 and 24 h after surgery and changes of haemodynamics before surgery, at the end of surgery and 12, 24 and 48 h after surgery were compared in the three groups. Besides, visual analogue scale (VAS) scores were recorded 4, 8, 12 and 24 h after surgery. Results: 12 and 24 h after surgery, the levels of plasma NE and Cor in three groups rose dramatically (P<0.05 or (P<0.01); The levels of plasma NE and Cor in trial groups I and II were evidently lower than in control group (P<0.05 or P<0.01), and those in trial group II slightly lower than in trial group I. 12 h after surgery, the heart rates (HR) and systolic pressures (SBP) in trial groups I and II increased obviously by comparison to surgery before (P<0.05 or P<0.01), but gradually returned to the preoperative level. HR, SBP and diastolic pressures (DBP) in trial groups I and II at the end of surgery and 12 h after surgery were all lower than in the control group, and significant differences were present (P<0.05 or (P<0.01). At 4, 8, 12 and 24 h after surgery, VAS scores in trial groups I and II were markedly lower than in the control group (P<0.05 or (P<0.01), the scores in trial group II being the lowest. Conclusions: Combined application of parecoxib sodium for preemptive analgesia before anesthesia and after surgery can effectively reduce the levels of plasma stress hormones and improve analgesic effects in surgical patients with thyroid carcinoma, and without conspicuous impact on haemodynamics.

• Toxicological Research
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• v.24 no.4
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• pp.281-287
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• 2008

Impairment of hepatic metabolism of sulfur-containing amino acids has been known to be linked with induction of liver injury. We determined the early changes in the transsulfuration reactions in liver of rats challenged with a toxic dose of $CCl_4$ (2 mmol/kg, ip). Both hepatic methionine concentration and methionine adenosyltransferase activity were increased, but S-adenosylmethionine level did not change. Hepatic cysteine was increased significantly from 4 h after $CCl_4$ treatment. Glutathione (GSH) concentration in liver was elevated in $4{\sim}8$ h and then returned to normal in accordance with the changes in glutamate cysteine ligase activity. Cysteine dioxygenase activity and hypotaurine concentration were also elevated from 4 h after the treatment. However, plasma GSH concentration was increased progressively, reaching a level at least several fold greater than normal in 24 h. ${\gamma}$-Glutamyltransferase activity in kidney or liver was not altered by $CCl_4$, suggesting that the increase in plasma GSH could not be attributed to a failure of GSH cycling. The results indicate that acute liver injury induced by $CCl_4$ is accompanied with extensive alterations in the metabolomics of sulfurcontaining amino acids and related substances. The major metabolites and products of the transsulfuration pathway, including methionine, cysteine, hypotaurine, and GSH, are all increased in liver and plasma. The physiological significance of the change in the metabolomics of sulfur-containing substances and its role in the induction of liver injury need to be explored in future studies.

• Korean Journal of Acupuncture
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• v.26 no.3
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• pp.43-54
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• 2009

Objectives : To investigate the anti-inflammatory effects of Prunella vulgaris pharmacopuncture in lipopolysaccharide (LPS)-induced inflammatory rat model. Methods : Sprague-Dawley rats were divided into 5 groups; normal control (n=8), LPS control (n=8), LPS+Prunella vulgaris pharmacopuncture at CV4 (CV4, n=8), LPS+Prunella vulgaris pharmacopuncture at ST36 (ST36, n=8), and LPS+Prunella vulgaris pharmacopuncture at CV12 (CV12, n=8). Pharmacopuncture was given every two days for 4 weeks followed by inflammation induction by peritoneal LPS injection (5mg/kg). Proinflammatory cytokines including interleukin-$1{\beta}$ (IL-$1{\beta}$), interleukin-6 (IL-6), tumor necrosis factor-$\alpha$ (TNF-$\alpha$), interleukin-10 (IL-10), thiobarbituric acid reactive substance (TBARS) from blood and liver tissue were compared before and 5 hrs after inflammation induction. Results : In CV4 and CV12 groups, plasma IL-$1{\beta}$, IL-6 and TNF-$\alpha$ levels increased by LPS injection, significantly decreased 5 hrs after injection (p<0.05). For CV12 group, plasma IL-10 concentration significantly increased (p<0.05). Liver IL-$1{\beta}$ and IL-6 levles significantly decreased in CV4 and CV12 groups (P<0.05), while normal and LPS control groups were not significantly different in TNF-$\alpha$ and IL-10 levels. Plasma TBARS concentration was significantly decreased in CV12 group, while there was no significant difference among LPS control and pharmacopuncture groups for liver TBARS concentration. Conclusions : Based on the present findings, Prunella vulgaris pharmacopuncture at CV12 may have a potentially preventive anti-inflammatory effect in an LPS-induced inflammatory rat model.

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.327-332
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• 1986

Spatial (radial and height) distribution of electron number density is measured for an inductively coupled plasma under five operating conditions: (1) no carrier gas, (2) carrier gas without aerosel, (3) carrier gas with aerosol, (4) carrier gas with desolvated aerosol, and (5) carrier gas with aerosol and excess lithium. A complete RF power mapping of electron density is obtained. The plasma electrons for a typical analytical torch are observed to be hollow at the radial center in the region close to the induction coil, but diffuse rapidly toward the center in the higher region of the plasma. The presence of excess Li makes no significant change in the electron density profiles. The increases in the RF power levels increase the values of electron density uniformly across the radial coordinate.