• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.253-261
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• 2005

Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.43-51
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• 2022

Regulation of the hair follicle cycle in association with dermal papilla cells is one of the most interesting targets for promoting hair regrowth. In this study, we examined whether steam-dried Betula platyphylla extracts (BPE) promote hair growth by upregulating in vitro and in vivo responses of dermal papilla cells. The data showed that BPE3 contained high amounts of phenolic compounds with higher antioxidant effects and increased hair growth-related genes, including fibroblast growth factor7 and Wnt7b, in dermal papilla cells. Notably, BPE3 effectively enhanced the formation of hair follicles by increasing FGF7, Wnt7b, and vascular endothelial growth factor in C57BL/6N dorsal skins. Additionally, BPE3 significantly decreased the expression of inflammatory repertoires, inducible nitric oxide synthase, interleukin-6, and cyclooxygenase 2. Several small molecules, such as betulin and unsaturated fatty acids, support the pharmacological activity of BPE3. In conclusion, BPE3 effectively promoted hair growth by activating dermal papilla cells and enhancing hair follicle cycles by attenuating the inflammatory environment in the scalp.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.494-503
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• 1995

The selection of salt tolerant rice variety needs an effective method in its testing. Salinity of irrigated water, 0.5% at seedling stage, 0.6% at tillering stage, and 0.9% at panicle formation stage were treated to test salt tolerance of rice using 45 cultivars. At tillering stage, salty water irrigation reduced plant height to 22.6% in early maturing rices(EMR), 30.5% in medium maturing rices(MMR), and 20.9% in medium-late maturing rices(MLMR), and also reduced number of tillers to 11.2% in EMR, 36.2% in MMR, and 36.0% in MLMR compared to rices grown in non-salty water irrigation. At panicle formation stage of rice, salty water irrigation affected plant height and tiller numbers that showed varietal differences. As salt tolerant rice cultivars, Daegwangbyeo, Namweonbyeo, Sinseonchalbyeo, Gyehwabyeo, and Daeyabyeo were selected. Jinbubyeo, Donghaebyeo, and Tamjinbyeo were weak in salty water irrigation.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.55-61
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• 2003

The objective of this study was to investigate the characteristics of nitrate removal by conducting the column test in order to see the performance of surfactant modified zeolite (SMZ) as a permeable reactive barrier material. The prediction of nitrate removal was tested using the one-dimensional advective-dispersive model fitted to the experimental breakthrough curve. A methodology for scaling up to in-situ permeable reactive barrier was also proposed. The breakthrough of nitrate in the column packed with SMZ was well predicted using linear equilibrium adsorption model. The breakthrough time and half-life obtained by breakthrough experiment with variation of flowrates were decreased with the increase of flowrates. When 10㎥/day of groundwater containing the 50 mg/l of nitrate is to be treated to satisfy the potable water quality criteria (10 mg/l) by SMZ reactive barrier, 300 tons of SMZ and about 6 years of breakthrough time will be required, suggesting that 165 million wons are needed as barrier material expenses in each 6 years besides the initial design and construction expenses and the minimal monitoring and maintenance expenses.

• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.10-16
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• 2015

Bone changes are common sequela of irradiation in growing animal. The purpose of this study was to establish an experimental model of radiation-induced bone loss in growing mice using micro-computed tomography (${\mu}CT$). The extent of changes following 2 Gy gamma irradiation ($2Gy{\cdot}min^{-1}$) was studied at 4, 8 or 12 weeks after exposure. Mice that received 0.5, 1.0, 2.0 or 4.0 Gy of gamma-rays were examined 8 weeks after irradiation. Tibiae were analyzed using ${\mu}CT$. Serum alkaline phosphatase (ALP) and biomechanical properties were measured and the osteoclast surface was examined. A significant loss of trabecular bone in tibiae was evident 8 weeks after exposure. Measurements performed after irradiation showed a dose-related decrease in trabecular bone volume fraction (BV/TV) and bone mineral density (BMD), respectively. The best-fitting dose-response curves were linear-quadratic. Taking the controls into accounts, the lines of best fit were as follows: BV/TV (%) = $0.9584D^2-6.0168D+20.377$ ($r^2$ = 0.946, D = dose in Gy) and BMD ($mg{\cdot}cm^{-3}$) = $8.8115D^2-56.197D+194.41$ ($r^2$ = 0.999, D = dose in Gy). Body weight did not differ among the groups. No dose-dependent differences were apparent among the groups with regard to mechanical and anatomical properties of tibia, serum ALP and osteoclast activity. The findings provide the basis required for better understanding of the results that will be obtained in any further studies of radiation-induced bone responses.

• Journal of Life Science
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• v.25 no.7
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• pp.786-794
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• 2015

To identify nutritional and therapeutic properties of the new Korean red waxy sorghum cultivar ‘Hwanggeumchalsusu (HGC)’, we assayed the antioxidative effects and neuraminidase inhibitory activity. A methanol and 70% ethanol extract of HGC exhibited strong antioxidative effects (IC₅₀ values of 83.2±2.7 for DPPH) and 85.6±2.4 μg/ml for ABTS) and neuraminidase (ND) inhibitory activity (IC₅₀ values of 1.8±0.1 from extracted with methanol and 3.4±0.1 μg/ml from extracted with 70% ethanol) compared with that of the control, noncolored sorghum cultivar ‘Huinchalsusu (HC)’ (IC₅₀> 200 μg/ml). We isolated nine polyphenols, Gallic acid (1), Protocatecuic acid (2), p-Hydroxy benzoic acid (3), Vanillic acid (4), Caffeic acid (5), Ferulic acid (6), Luteolinidin (7), Apigeninidin (8), Luteolin (9), from the HGC - methanol extract, to determine whether they were the active components Luteolinidin of one kind of polyphenols from the HGC, exhibited significant antioxidative effects (IC₅₀ values of 10.9±0.5 μM for DPPH and 8.6 0.6 μM for ABTS) and neuraminidase (ND) inhibitory activity (IC₅₀ values of 26.3±0.6) showed noncompetitive inhibition model. The binding affinity of the ND inhibitors in molecular docking experiments correlated with their ND inhibitory activities. These results suggest that HGC may be utilized to serve as a potential effective antioxidant and inhibitor of ND.

• Development and Reproduction
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• v.2 no.1
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• pp.45-52
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• 1998

An enhncer detector line(EDL) having P[1ArB] insertion in X chromosome with expression of reporter gene (lacZ) in the polar cells and border cell of egg chamber was established and used to monitor the differentiation and migration of border cells during the oogenesis of Drosophila. differentiation of border cell from the anterior polar follicle cells was evident in stage-9 egg chamber of EDL149 which was characterized by migration of columnar follicle cells toward posterior of egg chamber surrounding the oocyte. Migration of border cells was observed in the stage-9 and -10 egg chambers. \beta -galactosidase activities were rapidly increased during the first 4 days after eclosion, and it coincided with the timing of border cell differentiation in the ovary during adult life. Homozygote of EDL149 showed some retardation of border cell migration , resulting absence of migration of some border cells in the anterior part of egg chamber or delayed migration of some border cells in the stage-10 egg chamber. These results suggest that the P[1ArB] of EDL149 is inserted at the locus of the structural gene required for the border cell migration. In addition to the expression in egg chambers, lacZ expression was also detected in the meiotic germ cells of testis and antenna, suggesting the possible requirement of the trapped gene function in these organ. this EDL and enhancer trapped gene might be useful for the study of developmentally regulated cell migration.

• Journal of Environmental Science International
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• v.22 no.4
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• pp.463-469
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• 2013

This study was conducted to investigate the effects of the Cordyceps militaris extract on the improvement of the glucide metabolism in serum of streptozotocin (STZ, 50 mg/kg BW, IP injection)-induced diabetic rats (SD strain, male) fed the experimental diets for 5 weeks. Concentrations of creatinine, lipid peroxide and NEFA in sera were significantly higher in the STZ-induced diabetic group (group DMG) and STZ+Cordyceps militaris extract administration group (group DMS) than those in the control group (group BD). However, the concentrations of creatinine, lipid peroxide and NEFA in sera were reduced in the group DMS than those in the group DMG. The activity of creatine phosphokinase (CPK) in serum was lower in the group DMS than in the group DMG. The activity of LCAT in serum was increased in the group DMS (Cordyceps militaris extract administration) than in the group DMG. The results indicate that Cordyceps militaris extract were effective in the improvement of the glucide metabolism in the sera of STZ-induced diabetic rats.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.236-236
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• 1994

Acetylsalicylic acid (ASA)와 고려홍삼의 항산화 성분인 maltol을 축합하여 신물질 aspalatone을 합성하고, 흰쥐에서의 지혈시간 연장 효과, 항혈소판 응집 억제 (in Vitro, ex ViVO) 효과 및 생쥐의 혈전 모델을 이용한 항혈전 (in vivo) 효과를 연구하였다. SD계 웅성 흰쥐에 15 mg/kg의 낮은 용량으로 경구투여 할 경우, aspalatone과 ASA는 각각 최소한 8일 연속투여후 지혈시간을 유의적으로 연장시켰으며 같은 용량으로 10일 간 경구투여. 하였을 때, aspalatone 투여군은 대조군에 비하여 지혈시간이 57% (p<0.005) 연장된 반면, ASA 투여군은 44% 연장되었다. 반면, aspalatone의 아세칠 기를 갖지 않는 salicylic acid maltnl ester는 같은 용량에서 지혈시간을 유의적으로 연장시키지 않았다. Aspalatone은 in vitro에서 collagen에 의해 유도된 흰쥐 혈소판 응집을 강력하게 억제하였으나 (IS$_{50}$ = 0.18 mM), ASA와 마찬가지로 ADP에 의한 응집은 억제하지 않았다. Aspalatnne과 다른 대조약물들의 ex vivo에서의 혈소판 응집 억제능은 ASA>dipyridamdle(equation omitted)aspalatone>ticlopidine의 순이었다. 1회 경구투여로 aspalatone은 생쥐의 collagen에 의한 혈전에 기인하는 치사율을 억제하였다 (ED$_{50}$ = 32mg/kg). Aspalatone을 10일 간 투여하면 유효용량이 현저히 감소하여 20 mg/kg에서 치사율을 90% (p<0.001) 억제하였으며, 이러한 항혈전 효과는 투여중단 4일 후에도 지속되었다. 또한, 경구투여시 위궤양을 유발하는 ASA (ulcer index : 29 mm 200 mg/kg p.o.)와는 다르게 aspalatone은 위궤양을 유발하지 않는다는 장점을 갖는다 (0.71 mm, 800 mg/kg p.o.). In vitro에서 malondialdehyde 생성 억제를 지표로 한 aspalatone의 항산화 활성 ($IC_{50}$/ = 0.11 mM)은 maltol ($IC_{50}$/ = 0.084 mM)과 유산하다. 이러한 실험결과를 토대로 하여 aspalatone을 위궤양을 유발하지 않는 항혈전 신약으로 개발하기 위한 연구가 진행 중이다.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.728-739
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• 2005

An experiment and simulation were performed for hydrogen separation of mixtures by PSA (pressure swing adsorption) process on activated carbon. The binary ($H_2/Ar$; 80％/ 20％) and ternary ($H_2/Ar/CH_4$; 60％/ 20％/ 20％) mixtures were used to study the effects of feed composition. The cyclic performances such as purity, recovery, and productivity of 2bed-6step PSA process were experimentally and theoretically compared under non-isothermal and non-adiabatic conditions. The develped process produced the hydrogen with 99％ purity and 75％ recovery from both processes. Therefore, optimal separation condition was referred multicomponent gas mixtures.