• Bulletin of the Korean Chemical Society
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• v.2 no.2
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• pp.71-75
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• 1981

Vacuum ultraviolet photolysis of ethyl bromide was studied at 104.8-106.7 nm (11.4-11.6 eV) in the pressure range of 0.2-18.6 torr at $25^{\circ}$ using an argon resonance lamp with and without additives, i.e., NO and He. Since the ionization potential of $CH_3CH_2Br$ is lower than the photon energy, the competitive processes between the photoionization and the photodecomposition were also investigated. The observations indicated that 50% of absorbed light leads to the former process and the rest to the latter one. In the absence of NO the principal reaction products for the latter process were found to be $CH_4, C_2H_2, C_2H_4, C_2H_6, and C_3H_8$. The product quantum yields of these reaction products showed two strikingly different phenomena with an increase in reactant pressure. The major products, $C_2H_4$ and $C_2H_6$, showed positive effects with pressure whereas the effects on minor products were negative in both cases, i.e., He and reactant pressures. Addition of NO completely suppresses the formation of all products except $C_2H_4$ and reduces the $C_2H_4$ quantum yield. These observations are interpreted in view of existence of two different electronically excited states. The initial formation of short-lived Rydberg transition state undergoes HBr molecular elimination and this state can across over by collisional induction to a second excited state which decomposes exclusively by carbon-bromine bond fission. The estimated lifetime of the initial excited state was ${\sim}4{\times}10^{-10}$ sec. The extinction coefficient for $CH_3CH_2Br$ at 104.8-106.7 nm and $25{\circ}$ was determined to be ${varepsilon} = (1/PL)ln(I_0/I_t) = 2061{\pm}160atm^{-1}cm6{-1}$ with 95% confidence level.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.6
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• pp.337-341
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• 2006

The present study was designed to investigate the protein expression of nitric oxide synthase (NOS) and guanylyl cyclase (GC) activity in ischemia/perfusion (I/R) renal injury in rats. Renal I/R injury was experimentally induced by clamping the both renal pedicle for 40 min in Sprague-Dawley male rats. The renal expression of NOS isoforms was determined by Western blot analysis, and the activity of guanylyl cyclase was determined by the amount of guanosine 3', 5'-cyclic monophosphate (cGMP) formed in response to sodium nitroprusside (SNP), NO donor. I/R injury resulted in renal failure associated with decreased urine osmolality. The expression of inducible NOS (iNOS) was increased in I/R injury rats compared with controls, while endothelial NOS (eNOS) and neuronal NOS (nNOS) expression was decreased. The urinary excretion of NO metabolites was decreased in I/R injury rats. The cGMP production provoked by SNP was decreased in the papilla, but not in glomerulus. These results indicate an altered regulation of NOS expression and guanylyl cyclase activity in I/R-induced nephropathy.

• The Journal of Internal Korean Medicine
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• v.21 no.4
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• pp.535-542
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• 2000

The water extracts of Samul-tang(SMT) has been used for treatment of ischemic brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extracts of SMT rescues brain cells from ischemic damages. To elucidate the protective mechanism on ischemic induced cytotoxicity, I investigate the regulation of LPS and PMA induced iNOS expression in C6 glial cells. LPS and PMA treatment for 72 h in C6 glial cells markedly induce nitric oxide(NO), but treatment of the cells with the water extracts of SMT decrease. dose dependently nitrite formation. In addition, LPS and PMA treatment for 72 h induce severe cell death and LDH release in C6 glial cells. However treatment of the cells with the water extracts of SMT dose not induce significant changes compare to control cells. Furthermore, the protective effects of the water extracts of SMT is mimicked by treatment of $N^{G}MMA$, a specific inhibitor of NOS. LPS and PMA induced iNOS activation in C6 glial cells cause chromosomal condensation and fragmentation of nuclei by caspase activation. The treatment of the cells with the water extracts of SMT may suppress apoptosis via caspase inhibition by regulation of iNOS expression. Taken together, I suggest that the protective effects of the water extracts of SMT against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.4
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• pp.311-320
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• 2016

Kava (Piper methysticum, P. methysticum) is used as traditional herbal medicine for urogenital diseases, rheumatisms, gastrointestinal problems, respiratory irritations, and pulmonary pains. We identified a flavokavain C (FKC) from P. methysticum, which showed anti-inflammatory activity on nuclear factor ${\kappa}B$ (NF-${\kappa}B$)-dependent nitric oxide (NO) production and expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. FKC inhibited accumulation of reactive oxygen species (ROS), such as hydrogen peroxide, and was able to dose-dependently reduce the LPS-induced NO production and the expression of various inflammation-associated genes (iNOS, IL-$1{\beta}$, IL-6) through inhibition of NF-${\kappa}B$ and MAPKs (ERK and JNK). In conclusion, these results indicate that FKC may have the potential to prevent inflammation process including NF-${\kappa}B$ and MAPKs pathways, and it could be applicable to functional cosmetics for anti-inflammation and antioxidant properties.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.2
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• pp.266-271
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• 2014

The Electromagnetic Interference(EMI) generating from corona discharge of transformer area can interference the digital Instrument and Control(I&C) systems located nearby transformers. When the potential gradient of the electric field around the conductor is high enough to form a conductive region but not high enough to cause electrical breakdown to nearby objects, the EMI of corona discharge emits with the conducted and radiated noise and it interferences the signals of the I&C systems. Since digital I&C systems have an efficiency and competitive price, the analog I&C systems have been upgraded and displaced with the digital I&C systems but which have less EMI Immunity. There was no assessment to I&C systems by EMI generating corona discharge nearby transformers. When the safety-related I&C systems are installed in plants, the verification of equipment EMI should be done not in site-specific test but in test facilities. There are the need to do the site-specific EMI evaluation of corona discharge nearby transformers. This paper assesses the margin between plant emission limits and the highest composite plant emission of corona. When the non safety-related I&C systems are placed in transformer area, it suggests the appropriate radiated susceptibility level to EMI of corona discharge.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1123-1124
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• 2011

본 논문에서는 ESW(Electro slag welding)의 용접을 위한 해석을 수행하였다. 특히, 열전달 해석을 통하여 부재내부에 발생하는 온도분포에 대한 해석을 수행하였으며, 이를 입력조건으로 하여 구조해석을 수행함으로써, 최종적은 부재내의 최고온도와 최대 변형량을 구할 수 있었다.

• Parasites, Hosts and Diseases
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• v.42 no.4
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• pp.175-183
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• 2004

To evaluate the role of nitric oxide (NO) in $IFN-{\gamma}$ production and apoptosis of splenocytes in genetically different strains of mice with toxoplasmosis, BALB/c (a toxoplasmosis resistant strain) and C57BL/6 (a toxoplasmosis susceptible strain) mice were infected with Toxoplasma gondii cysts orally and subsequently injected intraperitoneally with aminoguanidine, an iNOS inhibitor (AG; 35 mg/kg per mouse daily for 14 days). When BALB/c or C57BL/6 mice were infected with T. gondii without AG treatment, number of brain cysts, NO and IFN-y production by splenocytes, and percentages of apoptotic splenocytes were increased compared to uninfected control mice without AG treatment. AG treatment increased the number of brain cysts, and reduced NO and $IFN-{\gamma}$ production in T. gondii-infected C57BL/6 mice. In contrast, in T. gondii-infected BABL/c mice, the number of brain cysts, and NO and $IFN-{\gamma}$ production of splenocytes was not altered by treatment with AG. However, the percentages of apoptotic splenocytes in T. gondii-infected BALB/c or C57BL/6 mice were not affected by AG treatment. These results suggest that NO modulates $IFN-{\gamma}$ production in T. gondii-infected C57BL/6 mice, and that NO is involved in mediating a protective response in toxoplasmosis susceptible, but not resistant, mice strain during acute infection.

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.316-325
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• 1997

In a 36-month period, 23 selected Patients with Acute Cerebral Infarction were studied utilizing Computerized Tomography, Barthel Index in an attempt to correlate Brain Computerized Tomography findings with 1week, 4weeks rehabilitation and evaluate the influences of the size and location of the lesion. The study suggested that the size of the lesion had impact on 4 weeks rehabilitation. There was significant different between the patients with Middle Cerebral Artery Pial Territory Infarction(I.P.B.M.C.A.) lesion and the patients with Lacunar Infarction(L.I.), Striatocapsular Infarction(S.C.I.), Internal Watershed Infarction(I.W.I.) lesion, but there was no significant difference between the patients with L.I. lesion and the patients with S.C.I. lesion and the patients with I.W.I. lesion. The size and location of the lesion should be considered together in predicting the functional outcomes of Acute Cerebral Infarction.

• Natural Product Sciences
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• v.18 no.3
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• pp.141-146
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• 2012

Veronica peregrina (Scrophylariaceae) has been widely used as a Korean traditional medicine for the treatment of various pathological conditions including infection, hemorrhage and gastric ulcer. In the current study, we investigated the inhibitory effect of methanolic extracts of V. Peregrina (VPM) on the LPS-mediated nitric oxide (NO) production in mouse (C57BL/6) peritoneal macrophages. NO production was significantly down-regulated by the treatment of VPM dose dependently. To evaluate the mechanism of the inhibitory action of VPM on NO production, we performed iNOS enzyme activity assay and checked the change of inducible nitric oxide synthase (iNOS) levels by Western blotting. Although VPM did not affect iNOS enzyme activity, iNOS protein expression was attenuated by VPM indicating VPM inhibits NO production via suppression of iNOS enzyme expression. In addition, VPM attenuated the expression of another pro-inflammatory mediator such as cyclooxygenase-2 (COX-2) in a dose dependent manner. We also found that VPM can reduce trypsin-induced paw edema in mice. Based on this study, we suggest that V. peregrina may be beneficial in diseases which related to macrophage-mediated inflammatory disorders.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.4 s.36
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• pp.281-291
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• 1990

Experiment I and II had done to develop the solar heat proof hat for field work in the summer. In the experiment I physical characteristics of several fabrics was tested to determine which one Is proper to make the solar heat proof hat. On the base of above results in the experiment II three improved solar heat proof hat was deviced and tested solar heat proof effect and compared the existing summer working hat by wearing trials in the environmental chamber. The results obtained were as follows. 1. In the view of the physical characteristics of six fabrics (Blue T/C, White poplin, Vapor transfer silver coating nylon taffeta, No vapor trans(or silver coating nylon taffeta, Aluminum coating T/C, Microporous fabric), the light color T/C and no vapor transfer silver coating nylon ta(feta is proper to make improved solar heat proof working hat. 2. Three improved hats that are made of white T/C, grey T/C and no vapor transfer silver coating nylon taffeta have more solar heat proof effect than the existing summer working hat. 3. Among the three improved hats, the improved hat that is made of no vapor transfer silver coating nylon taffeta is most effective to proof the solar heat.