• Proceedings of the KIEE Conference
• /
• 2004.04a
• /
• pp.18-20
• /
• 2004

This paper formulates the principle of the permanent magnetic actuator (PMA) and its dynamic characteristic calculation applicable to High Voltage Vacuum Interrupter (38kV/31.5kA). The new type of PMA is need to apply to High Voltage Vacuum Interrupter for large stroke length and contact force at interrupter. Consequently this paper describes the ideal matching of the new type of PMA mechanism with the characteristics required to operate successfully, reliably and efficiently a High Voltage Vacuum Interrupter.

• 한국방재학회:학술대회논문집
• /
• 2010.02a
• /
• pp.46.2-46.2
• /
• 2010

아스팔트 포장의 공용성능 행장을 위해 널리 사용되고 있는 폴리머 개질 아스팔트(PMA)는 높은 생산온도와 다짐온도로 인해 생산 시 연료 소비가 많고 시공관리가 어려운 단점을 가지고 있다. 이에 중온형 아스팔트 기술을 접목하여 고온에서의 아스팔트 점도를 낮춤으로써 이와 같은 문제점을 해결하고자 하였다. 바인더의 전반적 공용성능 향상을 위해서 폴리머 (SBR)와 작업성 개선을 위해 Wax 및 기타 첨가제를 혼합하여 아스팔트 바인더를 제조하였으며, 실험결과 PG 82-22의 높은 공용등급의 바인더를 얻었으며, 생산 및 시공온도는 기존의 PMA 아스팔트와 달리 일반 스트레이트아스팔트와 비슷한 수준을 확보하였다. 이를 이용한 아스팔트 혼합물의 공용 성능 면에서도 PMA개질 아스팔트와 비슷한 수준을 나타내었다.

• Archives of Pharmacal Research
• /
• v.18 no.6
• /
• pp.376-380
• /
• 1995

Monocyte adhesion involves specific cell surface receptors, integrins and results in cell differentiation. We have studied expression and regulation of integrin .${\alpha}_5{\beta}_1$ during differntiation of U937 as in vitro model. To determine expression of integrin ${\alpha}_5{\beta}_1$ during differentiation of U937 as in vitro model. To determine expression of integrin ${\alpha}_5{\beta}_1$ genes by RT-PCR (reverse transcription and polymerase chain reaction) method. We determined expression of integrin ${\alpha}_5{\beta}_1$ genes by RT-PCE (reverse transcription and polymerase chain reaction) method. We found that expression of integrin .alpha.5.betha.1 was greatly increased during PMA-induced differentiation of U937 cells and also found that PMA-induced expression of integrin ${\alpha}_5{\beta}_1$ was inhibited by colchicine, microtubule depoly merizing agent. These results indicate that microtubular integrity is associated with expression of integrin. ${\alpha}_5{\beta}_1$ during PMA-induced differentiation of U937 cells.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.2
• /
• pp.761-768
• /
• 2018

In this paper, the performance analysis of a control topology based on the direct output power control (DPC) for robust and inexpensive permanent magnet-assisted synchronous reluctance generator (PMa-SynRG) system is presented. The PMa-SynRG might be coupled to an internal combustion engine running at variable speed. A three-phase PWM rectifier rectifies the generator output and supplies the dc link. A single-phase PWM inverter supplies constant ac voltage at constant frequency to the grid. The overall control algorithm is implemented on a TMS320F2812 digital signal processor board. Simulations results and experimental results verify the operation of the proposed system.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1189-1191
• /
• 2005

This paper describes the design parameters for permanent magnet actuator(PMA). Recently, a PMA is great attention and increased in used. However, it needs a technique for applying design parameters in order to satisfy characteristics of PMA. In this paper, presented the design parameters for PMA that has both a mutual relation and a consideration for load.

• The Journal of Internal Korean Medicine
• /
• v.30 no.4
• /
• pp.685-695
• /
• 2009

Objectives : In this study, the author tried to investigate whether Geonpye-tang(GPT) significantly affects PMA-, EGF- or TNF-alpha-induced MUC5AC mucin production and gene expression from human airway epithelial cells. Materials and Methods : Effects of the agent on PMA-, EGF- or TNF-alpha-induced MUC5AC mucin production and gene expression from human airway epithelial cells (NCI-H292) were investigated. Confluent NCI-H292 cells were pretreated for 30 min in the presence of GPT and treated with PMA (10ng/ml) or EGF (25ng/ml) or TNF-alpha (0.2nM), to assess both effect of the agent on PMA- or EGF- or TNF-alpha-induced MUC5AC mucin production by enzyme-linked immunosorbent assay (ELISA) and gene expression by reverse transcription-polymerase chain reaction (RT-PCR). Possible cytotoxicity of the agent was assessed by examining the rate of survival and proliferation of NCI-H292 cells after treatment with the agent over 72 hrs (SRB assay). Results : (1) GPT significantly inhibited PMA-induced and EGF-induced MUC5AC mucin production from NCI-H292 cells. However, GPT did not affect TNF-alpha-induced MUC5AC mucin production. (2) GPT significantly inhibited the expression levels of PMA-, EGF- or TNF-alpha-induced MUC5AC genes in NCI-H292 cells (3) GPT did not show significant cytotoxicity to NCI-H292 cells. Conclusion : This result suggests that GPT can affect the production and gene expression of respiratory mucin observed in diverse respiratory diseases accompanied by mucus hypersecretion. This can explain the traditional use of GPT in oriental medicine. Effects of GPT with their components should be further investigated using animal experimental models that reflect pathophysiology of airway diseases through future studies.

• Environmental Analysis Health and Toxicology
• /
• v.15 no.3
• /
• pp.69-80
• /
• 2000

ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

• Clinical and Experimental Reproductive Medicine
• /
• v.21 no.1
• /
• pp.99-110
• /
• 1994

One consequence of fertilization in mammals is an increased resistance of the zona pellucida (ZP) to proteases and various chemical reagents. This phenomenon has been called 'zona pellucida hardening' (ZPH), and it is generally accepted that it is caused by the secretory products of cortical granules released by the egg at fertilization. ZP of mouse oocytes maturing in vitro in a chemically defined medium becomes progressively more resistant to solubilization by chymotrypsin ("Spontaneous" ZP hardening). In the present study, it was aimed to find the specificity of spontaneous ZPH in relation to its possible relevance to the cortical reaction and the physiological block to polyspermy. When a maturation inhibitors, cAMP analog(dbcAMP) and phosphodiesterase inhibitor (IBMX) was added to culture medium, it prevent spontaneous ZPH of mouse oocyte during in vitro culture. Thus spontaneous ZPH requires GVBD, since it is prevented by those agents, which inhibit GVBD in vitro. However, culture for 3 hours in the presence of PMA(lOng/ml), a protein kinase C activator, resulted in ZPH without GVBD, thus suggesting that ZPH may be regulated independently apart from the event of GVBD. Pretreatment of mouse oocyte with FBS result in partially inhibitory effect on subsequent spontaneous ZPH. Induction of GVBD in vivo had a inhibitory effect on the spontaneous ZPH, but subsequent spontaneous ZPH. Induction of GVBD in vivo had a inhinbitory effect on the spontaneous ZPII, but had no inhibitory effect on PMA-induced ZPH. Treatment with a microfilament formation blocker(cytochalasin-B) at 1${\mu}g$/ml concentration, resulted in the excellent inhibitory effect on spontaneous ZPH. However cytochalasin-B did not inhibit PMA-induced ZPH. Thus this suggesting that spontaneuse ZPH had a different mechanism from PMA-induced ZPH.

• The Korean Journal of Physiology and Pharmacology
• /
• v.7 no.6
• /
• pp.363-368
• /
• 2003

To gain insight on the role of pro-inflammatory cytokines in the pathogenesis and treatment of rheumatoid arthritis (RA), the phorbol 12-myristate 13-acetate (PMA)-induced IL-6 gene expression and the effect of caffeic acid phenethyl ester (CAPE) on the PMA-induced IL-6 gene expression were investigated in human fibroblast-like synoviocytes (FLSs). Synovial tissue samples were obtained from rheumatoid arthritis patients, and FLSs were isolated. The cells were stimulated with PMA (100 nM) for 6 hrs to induce IL-6 gene. The cells were pretreated with CAPE (20, 50, $100{\mu}M$) prior to PMA treatment. PMA increased IL-6 RNA expression, binding activities of transcription factors ($NF-{\kappa}B$, AP-1) to IL-6 promoter, and IL-6 promoter activity. However, CAPE inhibited PMA-induced IL-6 mRNA expression in dose-dependent manner, and also inhibited the increased binding activities of transcription factors to IL-6 promoter and IL-6 promoter activity. These results suggest that CAPE might regulate PKC-mediated IL-6 expression and inflammatory reactions in RA.

• The Korean Journal of Physiology and Pharmacology
• /
• v.17 no.1
• /
• pp.51-56
• /
• 2013

Many intracellular proteins and signaling cascades contribute to the sensitivity of N-methyl-D-aspartate receptors (NMDARs). One such putative contributor is the serine/threonine kinase, protein kinase C (PKC). Activation of PKC by phorbol 12-myristate 13-acetate (PMA) causes activation of extracellular signal-regulated kinase (ERK) and promotes the formation of new spines in cultured hippocampal neurons. The purpose of this study was to examine which PKC isoforms are responsible for the PMA-induced augmentation of long-term potentiation (LTP) in the CA1 stratum radiatum of the hippocampus in vitro and verify that this facilitation requires NMDAR activation. We found that PMA enhanced the induction of LTP by a single episode of theta-burst stimulation in a concentration-dependent manner without affecting to magnitude of baseline field excitatory postsynaptic potentials. Facilitation of LTP by PMA (200 nM) was blocked by the nonspecific PKC inhibitor, Ro 31-8220 ($10{\mu}M$); the selective $PKC{\delta}$ inhibitor, rottlerin ($1{\mu}M$); and the $PKC{\varepsilon}$ inhibitor, TAT-${\varepsilon}V1$-2 peptide (500 nM). Moreover, the NMDAR blocker DL-APV ($50{\mu}M$) prevented enhancement of LTP by PMA. Our results suggest that PMA contributes to synaptic plasticity in the nervous system via activation of $PKC{\delta}$ and/or $PKC{\varepsilon}$, and confirm that NMDAR activity is required for this effect.