• Environmental Analysis Health and Toxicology
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• v.6 no.3_4
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• pp.105-121
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• 1991

The object of this study is to investigate the toxicity of fenvalerate [(RS)-$\alpha$-cyano-3 -phonoxybenzyl-(RS)-2-(4-ch1orophenyl)-3-methylbutyrate] and the effect of carbaryl on the toxicity of fenvalerate. Rats were treated with fenvalerate (50 mg/kg, 100 mg/kg), carbaryl (50 mg/kg, 100 mg/kg) or mixtures of the two compounds (fenvalerate+carbaryl: 50 mg/kg+50 mg/kg, 50 mg/kg+100 mg/kg) by oral administration for 1~3 weeks. Control groups were treated with corn oil. The experimental results were summarized as follows. 1. LD$_{50}$ values of fenvalerate and carbaryl in male rats were 385 mg/kg and 625 mg/kg respectively. When 50 mg/kg and 100 mg/kg of carbaryl were administratrd, LD$_{50}$values of fenvalerate were 265 mg/kg and 225 mg/kg respectively. 2. Biochemical parameters such as ALT, LDH and glucose in serum were much more increased in the groups treated with mixture than the groups treated with either one of fenvalerate or carbaryl. 3. The groups treated with carbaryl and mixture for 3 weeks, the contents of cytochrome P-450 in the liver were significantly increased. In renal microsomal fractions, however, no significant changes of drug metabolizing enzyme activities were observed. 4. The activities of aniline hydroxylase in hepatic microsomal fractions were increased in the groups treated with fenvalerate and mixture and activity was much more increased in the groups treated with mixture. 5. The activities of ATPase in the groups treated with fenvalerate were decreased than that of groups treated with mixture. TBA values and the activity of glucose-6 -phosphatase in the liver were not significantly changed. 6. In mixture treated groups, the activities of cholinesterase in serum and in the liver were more decreased than those of carbaryl treated groups. The activities of carboxylesterase in serum in the liver were slightly increased in mixture treated groups, but in fenvalerate treated groups, the activities of carboxylesterase were much more increased than those of control groups. 7. As a result of this study, when carbaryl was as the synergist of fenvalerate, carbaryl inhibited the activities of esterases, so the toxicity of fenvalerate was increased.sed.

• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.389-394
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• 1994

8 X 10$^{6}$(viable cells/ml) of maximum cell density and 9000(IU/ml) of $\gamma$-IFN production were obtained at 55(ml/hr) of a perfusion rate by cultivating HSF cells using a moving membrane aeration bioreactor. This system proves to be an efficient culture process by maintaning 90% of viable cells during the whole cultivation periods. The metabolic molar quotient of glucose to lactate was 0.81 for overall ranges of glucose consumed while the evolution of ammonia was not linearly related to the consumption of glutamine. Low molar conversion ratio was observed in low consumptions of glutamine and high molar conversion ratio in high comsumptions. It also shows that the glutamolysis plays important role in the steady state conditions by evolving larger quantities of ammonia than lactate. At the above of 50 rpm, which is the optimum agitation speed for this bioreactor, the cell growth was severely affected while the IFN production was less decrea- sed, maintaing 1.5 X 10$^{-3}$(IU/cell/day) specific IFN production rate. The cumulatvie $\gamma$-IFN production was 7.2 X 10$^{8}$(IU) for 70 days of the cultivation, which yields 1 X 10$^{7}$ (IU/day) of IFN production rate. Therefore, a commercial production of $\gamma$-IFN by this culture process can be achievable by maintaining the above IFN productivity in a scaled-up culture system.

• Journal of Korean Society on Water Environment
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• v.25 no.1
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• pp.7-17
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• 2009

Soil and Water Assessment Tool (SWAT) was used to assess the impact of potential future climate change on the water cycle and soil loss of the Daecheong reservoir watershed. A sensitivity analysis using influence coefficient method was conducted for two selected hydrological input parameters and three selected sediment input parameters to identify the most to the least sensitive parameters. A further detailed sensitivity analysis was performed for the parameters: Manning coefficient for channel (Cn), evaporation (ESCO), and sediment concentration in lateral (LAT_SED), support practice factor (USLA_P). Calibration and verification of SWAT were performed on monthly basis for 1993~2006 and 1977~1991, respectively. The model efficiency index (EI) and coefficient of determination ($R^2$) computed for the monthly comparisons of runoffs were 0.78 and 0.76 for the calibration period, and 0.58 and 0.65 for the verification period. The results showed that the hydrological cycle in the watershed is very sensitive to climate factors. A doubling of atmospheric $CO_2$ concentrations was predicted to result in an average annual flow increase of 27.9% and annual sediment yield increase of 23.3%. Essentially linear impacts were predicted between two precipitation change scenarios of -20, and 20%, which resulted in average annual flow and sediment yield changes at Okcheon of -53.8%, 63.0% and -55.3%, 65.8%, respectively. An average annual flow increase of 46.3% and annual sediment yield increase of 36.4% was estimated for a constant humidity increase 5%. An average annual flow decrease of 9.6% and annual sediment yield increase of 216.4% was estimated for a constant temperature increase $4^{\circ}C$.

• Journal of The Korean Astronomical Society
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• v.46 no.6
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• pp.253-259
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• 2013

We present near-infrared light curves of HBC 722 after its the September 2010 outburst. We have been monitoring its near-infrared light curves since November 2010 with Korean Astronomy and Space Science Institute Infrared Camera System (KASINICS). HBC 722 exhibits large changes in optical and near-infrared brightness since its outburst. The J, H, and $K_s$ light curves over about 2.5 years show that in all observed bands HBC 722 progressively became fainter until around April 2011, down to J ~10.7, H ~9.9, $K_s$ ~9.3, but it is getting brighter again. Large scatter in the obtained light curve prevents us from finding whether there is any short timescale variation as reported in other optical observations. The near-infrared color of HBC 722 is becoming bluer since its outburst. The pre-outburst Spectral Energy Distribution (SED) of HBC 722 is consistent with that of a slightly reddened Class II YSO with the exception of the extraordinary IR-excess in the far-infrared region.

• Journal of the Korean Society of Costume
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• v.37
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• pp.211-230
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• 1998

Advertisements provide consumers with in-formation and knowledge about products and help a society to sustain homogeneity by actively reflecting important characteristics of mass culture. Yet this reflection is a selective and purposeful representation by the party of the fashion manufactures and carries the intention of stimulating and augmenting desire for commodities aiming to perpetuate capitalism. This study understood this selective reflection of mass culture by advertisements as a feature of hegemonic struggle between/fashion business and consumers and defined the values selected by advertisements as ideologies supporting the consumption ideology of capitalism. The purpose of this study was to examine the contents of the ideologies expressed in the clothing advertisements in women's magazines to persuade consumers into consumption. The method of study was mainly qualitative with subsidiary citations from the results of content analysis. The objects of analysis were clothing advertisements in 1996 issues of CeCi and Woman Sense, which were identified as the two most popular women's monthly magazines. The ideologies identified were ideologies concerning (1) Self Identity, (2) Sensibility, (3) Sex Role, (4) Globalism, (5) Youth, (6) Leas-ure and Pleasure. Repeated and insisted as natural and true, there values were proposed to be believed as common senses and studies re-port that values of advertisements are ac-cepted as more readily as they are more unreasonable, and the acts and behaviors expres-sed within advertisements are often imitated in real life situations. Therefore, it is highly probable that these values emphasized within advertisements are enacted in thoughts and behaviors of consumers' real life. Accordingly the author suggests that critical interpretation of advertisements is seriously required to fully understand the commodity ridden post industrial society of today and to lead a subjective life within it.

• Toxicological Research
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• v.35 no.2
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• pp.137-154
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• 2019

Triclosan (TCS) is an antimicrobial compound used in consumer products. The purpose of current study was to examine toxicology and risk assessment of TCS based on available data. Acute toxicities of oral, transdermal and inhalation routes were low, and phototoxicity and neurotoxicity were not observed. Topical treatment of TCS to animal caused mild irritation. TCS did not induce reproductive and developmental toxicity in rodents. In addition, genotoxicity was not considered based on in vitro and in vivo tests of TCS. It is not classified as a carcinogen in international authorities such as International Agency for Research on Cancer (IARC). No-observed-adverse-effect level (NOAEL) was determined 12 mg/kg bw/day for TCS, based on haematoxicity and reduction of absolute and relative spleen weights in a 104-week oral toxicity study in rats. Percutaneous absorption rate was set as 14%, which was human skin absorption study reported by National Industrial Chemicals Notification and Assessment Scheme (NICNAS) (2009). The systemic exposure dosage (SED) of TCS has been derived by two scenarios depending on the cosmetics usage of Koreans. The first scenario is the combined use of representative cosmetics and oral care products. The second scenario is the combined use of rinse-off products of cleansing, deodorants, coloring products, and oral care products. SEDs have been calculated as 0.14337 mg/kg bw/day for the first scenario and 0.04733 mg/kg bw/day for the second scenario. As a result, margin of safety (MOS) for the first and second scenarios was estimated to 84 and 253.5, respectively. Based on these results, exposure of TCS contained in rinse-off products, deodorants, and coloring products would not pose a significant health risk when it is used up to 0.3%.

• Toxicological Research
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• v.35 no.2
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• pp.131-136
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• 2019

Ethylhexyl dimethyl para-aminobenzoic acid (PABA) is an oily yellow liquid derivative of water-soluble PABA commonly used in sunscreen. Ethylhexyl dimethyl PABA is widely used as an ingredient in many cosmetics at an average concentration of 1.25% (0.5-2.0%) in Korea. Previous studies, including those involving animals, have demonstrated that ethylhexyl dimethyl PABA is toxic to the following four organs: testis, epididymis, spleen, and liver. In addition, experiments using human keratinocytes found that ethylhexyl dimethyl PABA inhibits cell growth and DNA synthesis at low concentrations, and halted the cell cycle of MM96L cells (human melanoma cell line) at the G1 phase. Despite limited clinical data in humans, many studies have confirmed increased mutagenicity of ethylhexyl dimethyl PABA following exposure to sunlight, which suggests that this molecule is likely to contribute to onset of sun-induced cancer despite protecting the skin through absorption of UVB. For risk assessment, the no observed adverse effect level (NOAEL) chosen was 100 mg/kg bw/day in a 4 weeks oral toxicity study. Systemic exposure dosage (SED) was 0.588 mg/kg bw/day for maximum use of ethylhexyl dimethyl PABA in cosmetics. Based on the risk assessment and exposure scenarios conducted in this study, the margin of safety (MOS) was calculated to be 180.18 for a sunscreen containing 8% ethylhexyl dimethyl PABA, which is the maximum level allowed by the relevant domestic authorities.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.49.1-49.1
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• 2021

We carried out simultaneous monitoring observations of five maser lines, H₂O (22 GHz), SiO 𝝊 =1, 2, J =1-0 (43.1, 42.8 GHz), and SiO 𝝊 =1, J=2-1, J =3-2 (86.2, 129.3 GHz), toward the Mira variable star WX Serpentis with the 21-m antennas of the Korean VLBI Network (KVN) in 2009-2021 (~12 years). Most spectra of the H₂O maser are well separated into two parts of two blue- and one redshifted features within ± 10 km s-1 of the stellar velocity. All detected SiO masers are generally concentrated within ± 5 km s-1 of the stellar velocity, and sometimes appear split into two components. Overall, the profiles of SiO and H₂O masers detected in WX Serpentis illustrate typical characteristics of the Mira variable. In addition, flux variations of both SiO and H₂O masers are well correlated with the optical light curve of the central star, showing a phase lag of ~ 0.1 for SiO masers and ~ 0.2 for H₂O maser. This phenomenon is considered to be the direct effect of propagating shock waves generated by the stellar pulsation, because SiO and H₂O masers are sequentially distributed at different positions with respect to the central star. In addition, we analyzed long-term trends and characteristics of maser velocities, maser ratio, and the velocity extents (the full width at zero power; FWZP). We also investigated a spectral energy distribution (SED) ranging from 1.2 to 240 ㎛ obtained using several infrared data: 2MASS, WISE, IRAS, ISO, COBE DIBRE, RAFGL, and AKARI (IRC and FIS). From the IRAS LRS and ISO SWS spectra of this star, we identified 9.7 and 12 ㎛ silicate emission features consistent with the SE6 spectrum model, corresponding to the typical AGB phase.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.702-708
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• 2011

There are considerable areas of wet paddy fields in Korea that requires improvement of its drainage system. In poorly drained sloping paddy fields, upland crops can be damaged by either rainfall or capillary rise of the water table caused by percolating water beneath the upper fields during summertime rainy season. The purpose of this study is to evaluate excess water stress of soybean yield by drainage systems. Four drainage methods namely open ditch, vinyl barrier, pipe drainage and tube bundle were installed within 1-m position at the lower edge of the upper paddy fields. Stress Day Index (SDI) approach was developed to quantify the the cumulative effect of stress imposed on a soybean yield throughout the growing season. SDI was determined from a stress day factor (SD) and a crop susceptibility factor (CS). The stress day factor is a measure degree and duration of stress of the ($SEW_{30}$). The crop susceptibility factor (CS) depends of a given excess water on crop stage. The results showed that SDI used to represent the moisture stress index was most low on the pipe drainage 64.75 compared with the open ditch 355.4, vinyl barrier 271.55 and tube bundle 171.55. Soybean grain yield increased continuously with the rate of 3% in Vinyl Barrier, 32% in Pipe Drainage and 16% in Tube Bundle.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.611-625
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• 2022

One of the applications of geomagnetic paleo-secular variation (PSV) is the age dating of archeological remains (i.e., the archeomagnetic dating technique). This application requires the local model of PSV that reflects non-dipole fields with regional differences. Until now, the tentative Korean paleosecular variation (t-KPSV) calculated based on JPSV (SW Japanese PSV) has been applied as a reference curve for individual archeomagnetic directions in Korea. However, it is less reliable due to regional differences in the non-dipole magnetic field. Here, we present PSV curves for AD 1 to 600, corresponding to the Korean Three Kingdoms (including the Proto Three Kingdoms) Period, using the results of archeomagnetic studies in the Korean Peninsula and published research data. Then we compare our PSV with the global geomagnetic prediction model and t-KPSV. A total of 49 reliable archeomagnetic directional data from 16 regions were compiled for our PSV. In detail, each data showed statistical consistency (N > 6, 𝛼₉₅ < 7.8°, and k > 57.8) and had radiocarbon or archeological ages in the range of AD 1 to 600 years with less than ±200 years error range. The compiled PSV for the initial six centuries (KPSV0.6k) showed declination and inclination in the range of 341.7° to 20.1° and 43.5° to 60.3°, respectively. Compared to the t-KPSV, our curve revealed different variation patterns both in declination and inclination. On the other hand, KPSV0.6k and global geomagnetic prediction models (ARCH3K.1, CALS3K.4, and SED3K.1) revealed consistent variation trends during the first six centennials. In particular, the ARCH3K.1 showed the best fitting with our KPSV0.6k. These results indicate that contribution of the non-dipole field to Korea and Japan is quite different, despite their geographical proximity. Moreover, the compilation of archeomagnetic data from the Korea territory is essential to build a reliable PSV curve for an age dating tool. Lastly, we double-check the reliability of our KPSV0.6k by showing a good fitting of newly acquired age-controlled archeomagnetic data on our curve.