• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.38-41
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• 2017

Reception performance in land mobile satellite is decreased by obstacle. It is compensated with Diversity technique. In this paper, performances are analyzed with two type of method Equal Gain Combining(EGC) and Selcetive Combining(SC). To analyze, measured data using On-The-Move(OTM) terminal are used. In conclusion, SC method can increase performance. However, EGC method can improve perforamance only in rural region, but performance are decreased in urban region.

• The Korean Journal of Pharmacology
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• v.16 no.2 s.27
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• pp.25-29
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• 1980

Etomidoline ($Nonspa^{\circledR}$), which is chemically related to tertiary amine, is new synthetic antispasmodic agent with analgesic action. Antispasmodic effect of this agent is stronger than hyoscine butylbromide ($Buscopan^{\circledR}$), quaternary amine, and the absorption from intestine is also much higher. This study was undertaken to determine the effect of etomidoline on duodenal motility and other smooth muscles of rabbit. Strips of various isolated smooth muscle, 2 cm long from adult rabbits weighting about 2 kg, were suspended in a muscle chamber containing Tyrode's solution, which was bubbled with oxygen gas, and the temperature of the solution was kept constant at $38^{\circ}C$. After being washed with fresh solution several times the strips of smooth muscle attained constant motility and tonus. Etomidoline and other drugs were added in various concentrations to the chamber. Contractility of the strips was measured by using polygraph (Grass, model 7). The results are as follows: 1) In isolated rabbit atrium etomidoline produces a slight depression of contractility and the rate is also decreased. 2) On the other hand, etomidoline relaxed isolated strips of stomach, duodenal, and detrusor of rabbit. This relaxing effect of etomidoline on isolated duodenal strip of rabbit was not blocked by ${\alpha}$-adrenergic blocking agent, phenoxybenzamine, but by ${\beta}$-adrenergic blocking agent, propranolol. 3) Etomidoline did not exert any effect on isolated aorta, gall bladder, and trigone of rabbit. From the above results, it may be concluded that the relaxing effect of etomidoline on duodenal strip is related ${\beta}$-adrenergic receptor.

• Journal of Korea Trade
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• v.27 no.5
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• pp.137-152
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• 2023

Purpose - Although many existing studies on the US-China hegemonic conflict and decoupling have been published, most of them are qualitative and use descriptive analysis methods. Papers that quantitatively analyzed decoupling mainly estimate the effect of a tariff increase. However, this paper quantitatively analyzed the ripple effect by focusing on decoupling technology spillover between the United States and China. And, for the first time, it was suggested that the blocking of technology spillover could give a fatal blow to the East Asian economy as well as China. Design/methodology - The United States is pursuing decoupling with China, primarily in goods trade and blocking technology transfer. This paper sets up various scenarios and uses three computational general equilibrium (CGE) models to analyze the overall ripple effects of decoupling. A paper using the three CGE models for decoupling ripple effect analysis has not yet been published. Findings - Decoupling will hit the economies of regions with close economic ties to China more than others. According to simulation results of this study, the Chinese economy may suffer severe damage that is difficult to recover from, and the economies of Asian countries are predicted to deteriorate to the point of being choked. Originality/value - Existing papers that assessed the effect of decoupling mostly focus on estimating the effect itself through tariff hikes. This paper is meaningful in that it comprehensively analyzed decoupling by adding the effect of technology spillover blockade. In addition, another meaning can be found in that it quantified for the first time that it will deal a huge blow to the extent of choking the East Asian economy as well as China.

• Molecules and Cells
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• v.27 no.5
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• pp.533-538
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• 2009

Heat shock protein 27 (Hsp27) is a molecular chaperone protein which regulates cell apoptosis by interacting directly with the caspase activation components in the apoptotic pathways. With the assistance of the Tat protein transduction domain we directly delivered the Hsp27 into the myocardial cell line, H9c2 and demonstrate that this protein can reverse hypoxia-induced apoptosis of cells. In order to characterize the contribution of Hsp27 in blocking the two major apoptotic pathways operational within cells, we exposed H9c2 cells to staurosporine and cobalt chloride, agents that induce mitochondria-dependent (intrinsic) and -independent (extrinsic) pathways of apoptosis in cells respectively. The Tat-Hsp27 fusion protein showed a greater propensity to inhibit the effect induced by the cobalt chloride treatment. These data suggest that the Hsp27 predominantly exerts its protective effect by interfering with the components of the extrinsic pathway of apoptosis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.4
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• pp.287-294
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• 2006

Vascular thrombosis and ischemic necrosis still remain the most significant threats to the survival of free flaps. To date, neutrophils have been implicated in the pathogenesis of postischemic injury. Several studies have demonstrated that modulating the neutrophil response to ischemia-reperfusion injury can decrease the extent of the injury. In addition, some authors noticed that mast cell counts were also increased in flaps exposed to state of ischemia/reperfusion. So, we designed to evaluate the role of mast cells in ischemia/reperfusion by blocking histamine and to compare the effect of L-arginine, a nitric oxide precursor which is known to prevent neutrophil-mediated tissue injury. Epigastric island skin flaps were elevated in 30 rats and rendered ischemic. Thirty minutes prior to reperfusion, the rats were treated with intraperitoneal saline, diphenhydramine, cimetidine, and L-arginine. The necrosis rate of flap at 7 days, the number of neutrophils and mast cells at 20 hours were evaluated. In conclusion, histamine receptor blockers as well as L-arginine significantly decreased flap necrosis in a rat skin island ischemia-reperfusion flap model, but the protective effect was not significantly different in both agent groups.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.10
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• pp.767-770
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• 2010

In this work, we investigated the static characteristics of 4H-SiC vertical metal-oxidesemiconductor field effect transistors (VMOSFETs) by adjusting the doping level of n-epilayer and the effect of a current spreading layer (CSL), which was inserted below the p-base region with highly doped n+ state ($5{\times}10^{17}cm^{-3}$). The structure of SiC VMOSFET was designed by using a 2-dimensional device simulator (ATLAS, Silvaco Inc.). By varying the n-epilayer doping concentration from $1{\times}10^{16}cm^{-3}$ to $1{\times}10^{17}cm^{-3}$, we investigated the static characteristics of SiC VMOSFETs such as blocking voltages and on-resistances. We found that CSL helps distribute the electron flow more uniformly, minimizing current crowding at the top of the drift region and reducing the drift layer resistance. For that reason, silicon carbide VMOSFET structures of highly intensified blocking voltages with good figures of merit can be achieved by adjusting CSL and doping level of n-epilayer.

• Natural Product Sciences
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• v.10 no.5
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• pp.211-216
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• 2004

Citrus unshiu (Rutaceae) has long been known as an anti-inflammatory and anti-allergic agent. In the present study, the inhibitory effect of CUWE (Citus unshiu water extract) on the production of $TNF-{\alpha}$ and tryptase was examined. In addition, a possible mechanism for the inhibition of trypsin-stimulated human leukemic mast cell-1 (HMC- 1 ) activation was determined. To do so, $TNF-{\alpha}$ production from the HMC-1 cells that were stimulated by trypsin (100 nM) in the presence or absence of CUWE $(10,\;100,\;and\;100\;{\mu}g/ml)$ was measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-PCR. The tryptase production was evaluated by reverse transcription-PCR. Extracellular signal-regulated kinase (ERK) activation was analyzed by Western blot. Trypsin activity was measured by using Bz-DL-Arg-p-nitroanilide (BAPNA) as substrate. Results showed that the CUWE inhibited production of both $TNF-{\alpha}$ and tryptase from the trypsin-stimulated HMC-1 in a dose-dependent manner. The CUWE a1so inhibited the ERK phosphorylation and trysin activity. These results indicate that the CUWE had an inhibitory effect on $TNF-{\alpha}$ and the tryptase productions by blocking the ERK phosphorylation and trypsin activity.

• Preventive Nutrition and Food Science
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• v.20 no.4
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• pp.221-229
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• 2015

Hesperidin has been shown to possess a potential inhibitory effect on vascular formation in endothelial cells. However, the fundamental mechanism for the anti-angiogenic activity of hesperidin is not fully understood. In the present study, we evaluated whether hesperidin has anti-angiogenic effects in mouse embryonic stem cell (mES)-derived endothelial-like cells, and human umbilical vascular endothelial cells (HUVECs), and evaluated their mechanism via the AKT/mammalian target of rapamycin (mTOR) signaling pathway. The endothelial cells were treated with several doses of hesperidin (12.5, 25, 50, and $100{\mu}M$) for 24 h. Cell viability and vascular formation were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and tube formation assay, respectively. Alteration of the AKT/mTOR signaling in vascular formation was analyzed by western blot. In addition, a mouse aortic ring assay was used to determine the effect of hesperidin on vascular formation. There were no differences between the viability of mES-derived endothelial-like cells and HUVECs after hesperidin treatment. However, hesperidin significantly inhibited cell migration and tube formation of HUVECs (P<0.05) and suppressed sprouting of microvessels in the mouse aortic ring assay. Moreover, hesperidin suppressed the expression of AKT and mTOR in HUVECs. Taken together, these findings suggest that hesperidin inhibits vascular formation by blocking the AKT/mTOR signaling pathways.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.1033-1043
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• 1997

In order to understand the generation mechanism of the Ulleung Eddy, we carried out a series of numerical experiments using the nonlinear 11/2 - layer model allowing the inflow of the Tsushima Current. According to our numerical results, the Ulleung Eddy was generated due to the inflow variations of the Tsushima Current. Its inflow through the Korea Strait was deflected to the east due to the Coriolis force and the nonlinear self advection. Thus, an anticyclonic motion was formed at the north of the Korea Strait. The inflow became a coastal boundary current, and finally flowed out model ocean through the eastern exit. When the speed of inflow decreased slowly, the eddy- like motion at the north of the Korea Strait changed into an enclosed anticyclonic eddy of about 200 km in diameter. The Ulleung Eddy became circular shape due to the nonlinear self advection, then changed into elliptical shape in meridional direction because of the blocking effect of the western boundary.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.764-767
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• 2002

To evaluate the osteotoxic effect of methylmercuric chloride(MMC) on cultured mouse osteoblasts, cytotoxic effect was measured by MTT assay after cultured mouse osteoblasts were incubated with various concentrations of MMC for 20 hours. The protective effect of Flos Carthami(FC) against MMC-induced osteotoxicity was also examined in these cultures. MMC decreased cell viability of cultured mouse osteoblasts remarkably in a dose- and time-dependent manners. In protective effect of FC was remarkably effective in blocking the osteotoxicity induced by MMC. From aboved the results, it is suggested that MMC induce osteotoxicity, and the selective herba extract such as FC is very effective in blocking MMC-mediated neurotoxicity on cultured mouse osteoblasts.