• Journal of the Korean Society for Precision Engineering
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• v.28 no.1
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• pp.115-122
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• 2011

Recently, we have proposed a hypothesis that spinal structures have a stress sensor driving feedback mechanism, In the human spine, spinal structure could react to modify muscular action in such a way so as to equalize stress at the disc, therefore reduce the risk of injury, In this analysis, abdominal muscle and abdominal pressure, which were not included in the previous study, were added to identify those effects in spine stability during upright stance posture for the case where the intervertebral disc plays the role of mechanoreceptor, The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Muscle architecture with 46 local muscles containing paraspinal muscle and 6 rectus abdominal muscles were assigned according to the acting directions. The magnitude of 4kPa was considered for abdominal pressure. Minimization of the nucleus pressure deviation and annulus fiber average tension stress deviation was chosen for cost function. Developed model provide nice coincidence with in-vivo measurement (nucleus pressure). Analysis was conducted according to existence of co-activation of abdominal muscle and abdominal pressure. Antagonistic activity of abdominal muscle produced stability of spinal column with relatively small amount of total muscle force. In contrast to the abdominal muscle, effect of abdominal pressure was not clear that was partly depending on the assumption of constant abdominal pressure.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.25-33
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• 2000

The new ion exchange resin was synthesized from chloromethylated styrene-1,4-divinylbenzene(DVB) with 1-aza-15-crown-5 macrocyclic ligand by substitution reaction. The effect of pH, time, dielectric constant of solvent and cross-linked of the matrix on the adsorption for $UO_2^{2+}$, $Ca^{2}$ and $Lu^{3+}$ was investigated. The metal ion was not adsorbed on the resins below pH 3 but above pH 4 fast adsorption behavior was showed. The optimum equilibrium time for adsorption of metallic ions was two hours. The adsorption selectivity determined in ethanol matrix was in increasing order $UO_2^{2+}>Ca^{2}>Lu^{3+}$. The adsorption power was in the order of 1%, 2%, 10% and 20% -crosslinked resin, but adsorption properties of resins decreased in proportion to the order of dielectric constant of solvents used. In addition, these metal ions could be separated in the column packed with 1% crosslinked resin by pH2.5 $HNO_3$ as an eluent.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.575-585
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• 2007

In this study, a new design equation was presented for square CFTs with high-strength concrete subjected to axial compression and bending. In a previous study, a design equation for square CFTs with normal strength concrete was proposed. A parametric study by fiber analysis was performed taking the width-to-thickness ratio (b/t) and the relative concrete strength to the yield strength of the steel tube (fck/Fy) as the main parameters of this study to determine the maximum moment and the axial load at the maximum moment. A new constitutive model for concrete was adopted for fiber analysis in order to take into account the effect of high-strength concrete. The results of the parametric study were embedded into the method which was presented in the previous study to formulate a new design equation that can be easily used for estimating the strength of square CFTs with high-strength concrete.

• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.489-496
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• 2013

Ground water underlying soil is vulnerable to pollution by organic chemicals through their percolation through the soil system. This study was conducted to provide information on the seepage behavior of organic chemical contaminants in clay, silty and sandy soils. Chloroform, 1,1,1-trichloroethane and trichloroethylene are readily transported through the soil; their percolated mass were 4.6-19.2 percent of the total mass applied. Tetrachloroethylene, 1,2-dichlorobenzene and 1,3-dichlorobenzene were retarded by soils due to sorption. Between 0.6 and 4.8 percent of the material applied to the surface percolated within the experimental period. Carbon tetrachloride was attenuated considerably by passage through soils. Only 0.1-0.4 percent of the mass reached the groundwater. Significant degradation of bromoform was observed. Apparent breakdown of intermediates of the brominated compounds were detected. Transformations of the brominated compounds appear to be the result of both biological and chemical processes. The effect of soil type on the mobility of organic chemical contaminants was considerable. The organic contaminants moved faster in sandy soil than in either clay or silty soils.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.142-144
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• 2004

The effect of hot water and methanol extracts of 9 species from Korean mushrooms (Fomitopsis pinicola, Fomitella traxinea, Codyceps militaris, Phellinus linteus, Coriolus versicolor, Sparassis crispa, Ganoderma lucidum, Fomes fomentarius, Agaricus blazei) on the growth of Helicobacter pylori were examined using a Mueller-Hinton agar diffusion method. Hot water ($121^{\circ}C$) extracts from fruit bodies of F. traxinea, C. militaris, P. linteus, C. versicolor and F. pinicola showed $10{\sim}15\;mm$ inhibition zone against H. pylori. Methanol extracts of F. pinicola showed 44 mm inhibition zone, but another extracts showed no inhibition. Early fractions of DEAE-Sephadex A-25 column chromatography of methanol extracts from F. pinicola showed high inhibition activity against H. pylori.

• The Korea Journal of Herbology
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• v.25 no.3
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• pp.65-71
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• 2010

Objectives：To develop and validate HPLC-PDA methods for simultaneous determination of seven constituents in Samchulkunbi-tang (SKT). Additionally, we investigated the cytotoxicity against BEAS-2B cell line and splenocytes of SKT. Methods：Reverse-phase chromatography using a Gemini $C_{18}$ column operating at $40^{\circ}C$, and photodiode array (PDA) detection at 230, 254 and 280 nm, were used for quantification of the three marker components of SKT. The mobile phase using a gradient flow consisted of two solvent systems. Solvent A was 1.0% (v/v) aqueous acetic acid and solvent B was acetonitrile with 1.0% (v/v) acetic acid. The cytotoxicity of SKT were measured by the CCK-8 assay method. Results：Calibration curves were acquired with $r^2$>0.9999, and the relative standard deviation (RSD) values (%) for intra- and inter-day precision were less than 6.0%. The recovery rate of each compound was in the range of 86.89-109.78%, with an RSD less than 4.0%. The contents of seven compounds in SKT were 1.39-6.84 mg/g. SKT had no cytotoxicity effect at 50-200 ${\mu}g$/mL concentrations. Conclusions：The established method will be helpful to improve quality control and in vitro efficacy study of SKT.

• Korean Journal of Pharmacognosy
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• v.30 no.4
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• pp.355-362
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• 1999

New lectins have been isolated and purified from mung bean (Phaseolus radiatus) through physiological saline extraction, ammonium sulfate salt fractionation and column chromatographies. Ion exchanger were eluted by linear salt gradient and then further purified through gel filtration. Thus obtained lectin named as MBL. The gene expressions of 5 cytokines (IL-1, IL-2, IL-6, $TNF-{\aphpa}$ and $IFN-{\gamma}$) from human peripheral blood mononuclear cells (PBMC) stimulated with MBL were investigated by using reverse transcription polymerase chain reaction (RT-PCR). PBMC ($1{\times}106$ cells/ml) isolated from healthy volunteers were stimulated with lectins (4 mg/ml) for various time intervals (1 to 96 hrs). After each of the various stimulated times, total RNA was isolated and assessed for different cytokines mRNA by RT-PCR. The mRNA encoding IL-1, IL-2 were detected continuously from 1 to 20 hrs, and IL-6 was detected up to 24 hrs. But the mRNA encoding $IFN-{\gamma}$ and $TNF-{\alpha}$ were detected to 8 hours only and showed short time response compared with other cytokines. The significant expression of all cytokines mRNA were observed at 4 hrs. These results suggested that MBL, as inducer of cytokines could elicit detectable cytokine mRNA from PBMC.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.51-58
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• 2005

Moment frames have been widely used in building construction. In current design codes, concrete moment frames are classified into ordinary, intermediate, and special moment resisting concrete frames (OMRCF, IMRCF, SMRCF)). The objective of this study is to investigate the seismic behavior of columns in ordinary moment resisting concrete frames (OMRCF) and intermediate moment resisting concrete frames (IMRCF). For this purpose 3 story OMRCF and IMRCF buildings were designed and detailed in compliance to ACI 318 (2002) and KCI (1999). In this study the buildings were assumed to be located in seismic zone 1 classified by UBC (1997). This study considered the columns in the 1st story since these columns shall resist the largest axial and lateral forces during an earthquake. Eight 2/3 scale column specimens were made for representing the upper part and lower part of exterior and interior columns of the OMRCF and the IMRCF Quasi-static reversed cyclic loading was applied to each specimen with a constant or varying axial load. Test results show that seismic behaviors of columns are influenced by existence of lap splices, axial force levels, and lateral reinforcement at possible plastic hinging region. However, the effect of such variables strongly co-related to each other.

• Journal of Nutrition and Health
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• v.19 no.6
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• pp.374-381
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• 1986

The effects of the hormonal factor (CCK) a and neural factor(carbachol) on the exocrine function of the pancreas were studied in th is experiment. A superfusion technique was used for in vitro study of stimulus-secreti- o on coupling in isolated pancreatic acinarce 11s frQm the rats fed heated or raw soybean diet. Chymotrypsin secretion was higher in cells from the raw soybean group than in those from the heated soybean group with both kinds of stimulants(CCK and carbachol), whereas, amylase secretion was higher inthe h heated soybean group than in the raw soy­b bean group. This indicated that chymotrvpsin a and amylase secretion from the acinar cells are not parallel with CCK and carbachol st­i imulation.

• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.349-353
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• 2007

Skin wrinkle formations are associated with collagen synthesis and matrix metalloproteinase-I(MMP-1) activity. This study was carried out to find out skin wrinkle reducing components in Torilis Fructus. Torilis Fructus were extracted with 70% ethanol and the ethanol extracts were systematically fractionated with n-hexane, ethylacetate, n-butanol and distilled water. Among them, antiwrinkle component from n-hexane fraction was purified by several column chromatographies and HPLC, which identified as torilin by $^1H-NMR,\;^{13}C-NMR$ and ESI-MS. To determine cell viability, collagen biosynthesis and MMP-1 activity, human dermal fibroblast was treated with 1-5 ppm concentrations of Torilis Fructus extract fraction and torilin. Cell viability was showed 84-102% at all group treated with 1-5 ppm. Collagen synthesis was increased in all group, especially torilin-treated group was highest amount. Active forms of MMP-1 were decreased in all group. From these results, we consider that Torilis Fructus have several antiwrinkle components and torilin may be one of the effective components.