• Structural Engineering and Mechanics
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• v.67 no.2
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• pp.143-153
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• 2018

Thermal buckling of nonlocal flexoelectric nanoplates incorporating surface effects is analyzed for the first time. Coupling of strain gradients and electrical polarizations is introduced by flexoelectricity. It is assumed that flexoelectric nanoplate is subjected to uniform and linear temperature distributions. Long range interaction between atoms of nanoplate is modeled via nonlocal elasticity theory. The residual surface stresses which are usually neglected in modeling of flexoelectric nanoplates are incorporated into nonlocal elasticity to provide better understanding of the physic of problem. A Galerkin-based approach is implemented to solve the governing equations derived from Hamilton's principle are solved. The verification of obtained results is performed by comparing buckling loads of flexoelectric nanoplate with previous data. It is shown that buckling loads of flexoelectric nanoplate are significantly affected by thermal loading type, temperature change, nonlocal parameter, surface effect, plate thickness and boundary conditions.

• Journal of Sensor Science and Technology
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• v.28 no.1
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• pp.17-22
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• 2019

As CMOS technology scales down, reliability is becoming an important concern for VLSI designers. This paper analyzes gate-oxide breakdowns (i.e., the time-dependent dielectric-breakdown (TDDB) aging effect) as a reliability issue for combinational circuits with 45-nm technology. This paper shows simulation results for the noise margin, delay, and power using a single inverter-chain circuit, as well as the International Symposium on Circuits and Systems (ISCAS)'85 benchmark circuits. The delay and power variations in the presence of TDDB are also discussed in the paper. Finally, we propose a novel method to compensate for the logic failure due to dielectric breakdowns: We used a higher supply voltage and a negative ground voltage for the circuit. The proposed method was verified using the ISCAS'85 benchmark circuits.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.141.1-141.1
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• 2003

The inhibitory effect of 13(E)-Labd-13-ene-8$\alpha$ 15-diol(1), isolated from the ethanol extract of Brachyglottis monroi, on the proliferation of human breast cancer MDA-MB231 cells was examined. Compound (1) at concentration as high as 16$\mu$/$m\ell$ has inhibited the proliferation of MDA-MB231 and this cytotoxic effect was increased in a time and dose-dependent manners. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.68.3-69
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• 2003

Matrix metalloproteinases (MMPs) play an important role in tumor invasion and metastasis by extracellular matrix degradation. To analyze the effect of DA-125, a anthracyclin derivative, on the invasion or metastasis of cancer cells the expression of matrix metalloproteases (MMPs) was investigated in human fibrosarcoma HTl080 cells by RT-PCR or gelatin zymographic methods. As result, DA-125 suppressed the expression of MMP-2 and 9 as well as tissue inhibitor of metalloproteinase-1 (TIMP-1) TIMP-2 and MT1-MMP with a time- and dose-dependent manner. Inaddition, DA-125 inhibited cancer cell migration and colony formation, and also exhibited the inhibitory activities of invasion and motility with a matrigel and type I collagen assay. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.246.1-246.1
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• 2002

We studied the effects of ursodeoxycholic acid (UDCA) and its synthetic derivatives. HS-l030 and HS-1183. and chenodeoxycholic acid (CDCA) and its synthetic derivatives, HS-1199 and HS-1200. on the human colon adenocarcinoma cell line. HT -29 (p53 mutant type). The effects on cell viability and growth were assessed by MTT assay and cell growth study. While UDCA and CDCA exhibited no significant effect, their novel derivatives inhibited the proliferation of HT-29 cell line in a concentration- and time-dependent manners. (omitted)

• Korea Trade Review
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• v.45 no.2
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• pp.17-29
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• 2020

This study analyzed that the effects of AEO MRA benefit on decreasing of trade cost and the strategies for expanding of trade. It uses the system GMM for effective solutions of endogenous matter with lagged dependent variable. In terms of the result of analysis, AEO MRA has a positive effect on decreasing of trade cost, especially this study proved the result of previous study AEO MRA expanded the trade through improving the time required for customs clearance and deregulation of non-tariff barriers. In conclusion, this study proposes the policy fo AEO MRA by analyzing the trade cost of AEO MRA by using the system GMM.

• Biomedical Science Letters
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• v.14 no.1
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• pp.27-32
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• 2008

To clerify the antioxidant effect of Crataegi Fructus (CF) extract on reactive oxygen species (ROS), The C6 glioma cells were treated with various concentrations of hydrogen peroxide ($H_2O_2$). The $H_2O_2$-induced neurotoxicity was measured by XTT assay for the cell viability. For the protective effect of CF extract on the cytotoxicity induced by $H_2O_2$, cell viability, lactate dehydroganase (LDH) activity, and the inhibitive activity of lipid peroxidation of CF extract were performed. In this study, $H_2O_2$ decreased cell viability dose- and time-dependent manners and increased LDH activity compared with the control. In the protective effect on $H_2O_2$, CF extract increased cell viability and decreased LDH activity on $H_2O_2$-induced cytotoxicity, lipid peroxidation by FTC assay. From these results, It is suggested that $H_2O_2$ was highly toxic on cultured C6 glioma cells, and also, CF extract showed the protective effect on $H_2O_2$-mediated cytotoxicity.

• Biomedical Science Letters
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• v.14 no.1
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• pp.33-38
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• 2008

In order to examine oxidative stress of reactive oxygen species and the antioxidant effect of Citri Reticulatae Pericarpium (CRP) extract, human skin melanoma cells were treated with various concentrations of hydrogen peroxide ($H_2O_2$). Antioxidant effect of CRP extract on $H_2O_2$-induced cytotoxicity, cell viability, DPPH-radical scavenging activity and superoxide dismutase (SOD)-like activity. In this study, $H_2O_2$ decreased cell viability of cultured human skin melanoma cells in dose- and time-dependent manners, and then, midcytotoxicity value (MCV) was determined at $60\;{\mu}M$ after human skin melanoma cells were cultured for 5 hours in the media containing $20{\sim}60\;{\mu}M$ of $H_2O_2$, respectively. The $H_2O_2$ was on cultured human skin melanoma cells because MCV of $H_2O_2$ was lower than $100\;{\mu}M$. In the antioxidant effect of CRP extract, CRP extract increased cell viability DPPH-radical scavenging activity and SOD-like activity. From these results, it is suggested that $H_2O_2$ was very toxic on cultured human skin melanoma cells. And also, CRP extract has the antioxidant effect on $H_2O_2$-induced cytotoxicity.

• The Journal of Internal Korean Medicine
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• v.18 no.1
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• pp.147-155
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• 1997

This study was undertaken to determine whether Salviae-radix (SVR) exraction exerts benefical effect against oxidant-induced inhibition of tetraethylammonium (TEA) uptake which is actively secreted by renal proximal tubules. TEA uptake increased as function of incubation time to 60 min. When renal cortical slices were exposed to 50 mM $H_2O_2$, TEA uptake was significantly inhibited. The inhibition was significantly protected by addition of 0.5% SVR extraction. The benefical effect of SVR was dose-dependent over the concentration range of 0.1-1%; $H_2O_2$ (50 mM)-induced inhibition of TEA uptake was completely protected by 0.5-1% SVR extraction. $H_2O_2$ increased LDH release which was accompanied by an increase in lipid peroxidation in renal cortical slices. These changes were prevented by 0.5% SVR. These results suggest that SVR exerts benefical effect against oxidant-induced impairment of membrane transport function, this effect may be due to by an antioxidant action.

• Atmosphere
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• v.20 no.4
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• pp.437-449
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• 2010

The relocation effect of observation station (REOS) on the homogeneity of seasonal mean of maximum and minimum temperature, diurnal temperature range (DTR) and relative humidity (RH) was investigated using surface observation data and document file. Twelve stations were selected among the 60 stations which have been operated more than 30 years and relocated over one time. The data from Chunpungryeong station were used as a reference to separate the impacts of station relocation from the effects caused by increased green house gases, urbanization, and others. The REOS was calculated as a difference between REOS of relocated station and REOS of reference station. Although the REOS is clearly dependent on season, meteorological elements, and observing stations, statistically significant impacts are found in many stations, especially the environment of observing station after relocation is greatly changed. As a result, homogeneity of seasonal mean of meteorological elements, especially DTR and RH, is greatly reduced. The results showed that the effect of REOS, along with the effect of urbanization, should be eliminated for the proper estimation of climate change from the analysis of long-term observation data.