• Journal of Pharmaceutical Investigation
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• v.31 no.4
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• pp.225-232
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• 2001

The present study was carried out to observe the effect of liposome dispersed gel formulation (Lipogel) on topical delivery of ascorbyl palmitate (AsP). Neutral and negatively charged MLV liposomes containing AsP were prepared with dimyristoylphosphadtidylcholine (DMPC) and dicetyl phosphate (DCP), and dispersed to poloxamer gel matrix. In the hydrolysis study in rat's skin homogenates, AsP hydrolyzed to ascorbic acid (AsA) according to the first-order kinetics with the rate constant of $2.46{\times}10^{-2}\;min^{-1}$. In the passive skin penetration study using Franz diffusion cell, lipogel systems exhibited the greater values in the flux $(J_s)$ and the amount penetrated $(Q_p)$ compared to control hydrogels containing diethyleneglycol monoethyl ether $(Transcutol^{\circledR})$ as a solubilizing agent and a penetration enhancer for AsP. The total amount penetrated $(Q_{Total})$, which is expressed as a summation of $Q_P\;and\;Q_L$, for lipogel system was about 1.4 times higher in average than that of control hydrogel. However the amount localized in the skin $(Q_L)$ was similar in both formulations. As a result, lipogel system enhanced the skin penetration of AsP, possibly due to the increase in local concentration of AsP by preferential adsorption of liposome to the skin and the enhancing effect of phospholipid in liposome composition. Moreover it was expected that the penetrated AsP would generate AsA during skin penetration by the skin esterase. In conclusion, lipogel formulation was considered as a good candidate for topical delivery of AsP.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.426-434
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• 2008

A space averaged $SiH_4/O_2/Ar$ simulator for the high density inductively coupled plasma sources for $SiH_4/O_2/Ar$ discharge is developed. The developed simulator uses space averaged fluid equations for electrons, positive ions, negative ions, neutral species, and radicals in $SiH_4/O_2/Ar$ plasma discharge, and the electron heating model including the anomalous skin effect. Using the developed simulator, the dependency of the density of charged particles, neutral particles, and radicals, the electron temperature, the plasma resistance, and the power absorption coefficient for the RF power and pressure is calculated.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.65-74
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• 2005

The negative skin friction on piles, which are installed in currently consolidating soft deposits, creates significant problems on the stability of pile foundations. This study investigated whether or not the pile foundation designs were appropriate in soft deposits with large amount of consolidation settlement. The final settlements of the grounds along the pile depth were estimated by the soil parameters obtained from the laboratory tests and by the field-measured settlement curves, if they were available. The displacement of the piles along the pile depth was estimated by both the load transfer method and the numerical method. Both methods gave similar locations of neutral planes and magnitudes of the maximum axial forces on the piles. The movements of the ground and the piles were compared to calculate the down drag acting on piles. For the piles whose bearing capacities were less than the design loads including the down drag, slip layer coatings and/or incrementing of the pile penetration depth into the bearing stratum were proposed to improve the pile capacities.

• Korean Journal of Human Ecology
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• v.16 no.1
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• pp.145-157
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• 2007

The purpose of this study was to identify Chinese university women's appearance management characteristics and clothing purchasing behavior. A self-administered questionnaire was used. Research period was 15th - 30th March. Frequencies, percent, factor analysis, cluster analysis, ANOVA, chi-square test were done. The results of study were: 1. The factors of appearance management characteristics were food management, skin care, weight control & tooth correction, nail & hair care, and use of identity kits. The factors of clothing selection criteria were outlook & appropriateness, management & service, fashion & brand, and individuality & price, and factors of information resources were marketer oriented & neutral and consumer oriented & store. 2. Chinese university women were segmented into positive appearance management group, food & skin management group, nail care & identity kits using group, and appearance management stagnated group. Positive appearance management group selected their clothing to pursuit individuality & relaxation, fashion, and conformity, considered fashion or brands more, used various information sources. Food & skin management group purchased their clothing for conformity. Nail care & identity kits using group considered management & service of clothing more, utilized consumer oriented & store information more. 3. Positive appearance management group were younger, and spent more pocket money and for their appearances. Food & skin management group were older, but nail care & identity kits using group were older. Appearance stagnated group spent less pocket money and appearance management.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.182-190
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• 2018

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4-fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

• Journal of fish pathology
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• v.9 no.2
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• pp.157-168
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• 1996

In this study, Residue of formaldehyde and histopathological changes in formalin and neutralformalin in treated fish(Sebastes schlegeli) were observed at two different temperatures(15 and $25^{\circ}C$). Immediately after in treatment, residue of formaldehyde in formalin treated fish was show little bit higher than in neutral-formalin treated fish at $15^{\circ}C$. But, there is no difference at water temperature $25^{\circ}C$. The elimination of formaldehyde was markedly temperature-dependent. The approximated withdrawal time were 72hr and 24hr at water temperature 15 and $25^{\circ}C$. Formalin was more toxic than the neutral-formalin at the same condition. Intensity of tissues damage was increased with increasing concentration of chemical and temperature. Formalin and neutral-formalin treatments caused edema and seperation of epithelium, winding of secondary gill lamella, necrosis in the gill ; congestion and pycnosis, vacuolation in the liver ; hydropic and granulated degeneration, necrosis of epithelial cells in the proximal renal tubule ; increasing mucus cells, cracking, necrosis of epidermis and dermis in the skin tissue.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.109-109
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• 2001

In order to evaluate the neutral red uptake assay as an alternative method for phototoxicity test, we compared the potential of phototoxicity in vitro in cultured human fibroblasts and 3T3 fibroblast cells derived from Balb/c mice. Both fibroblasts were exposed to various known phototoxic chemicals (promethazine, neutral red, chlorpromazine, chlortetracycline, amiodarone, bithionol, 8-methoxypsoralen) and non-phototoxic chemical (ammonium laureth sulfate) and irradiated with 5 J/cm$^2$ of UVA.(omitted)

• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.264-270
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• 1997

This Study was carried out develop antitumor effect of the n-butanol soluble of fraction of Perilla frutescens on human skin melanoma cells. The antitumor activity of various fractions obtained form n-butanol soluble fraction of Perilla frutescens was evaluated in human skin melanoma cells. The antitumor activity of the n-butanol soluble fraction in human skin melanoma cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, neutral red (NR) assay and sulforhordamine B protein (SRB) assay of colorimetic assay methods. The light microscopic study was carried out to observe morphological changes of cultured human skin melanoma cells. These results were obtained follows; The fractions 5 and 6 of the n-butanol soluble fraction of P frutescens were shown significant antitumor activities. The number of human skin melanoma cells were decreased and tend to form cell cluster by treatment with actions 5 and 7 of the n-butanol soluble fraction of P. frutescens. The fraction 6 of the the n-butanol soluble fraction showed the highest antitumor activity on P. frutescens. These results suggest that the fraction 6 of the n-butanol soluble fraction of P. frutescens may be a valuable choice for the studies on the treatment of human skin tumors.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.207-216
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• 2021

This study was conducted on 315 women in their 20s and 40s living in Changwon, South Gyeongsang Province, and recorded in a self-recorded format using the questionnaire survey method. In this study, the skin type according to the skin condition was not applied for 30 minutes after washing and checking the cheek area through the examination method to distinguish it by intelligence, neutral, dryness and boredom to see the interaction with each condition. The X2-test was conducted to find out the relevance between each factor and the data processing was done using PC/SAS. We reached at following conclusions. We can find some connections between skin condition and age, job, marriage by statistics(p<0.01). Each value of X2-TEST was 42.961(p<0.001) and 7.345(p<0.05). The pimples are shown after stress on cheek, chin and around neck easily. We also find some connections between skin trouble reaction and the beginning of pimple shown time(p<0.01).

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.317-317
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• 2000

The mathematical set-up model was developed to reduce the mechanical property deviation in annealed and slightly rolled steel strip. The mechanical peculiarities of temper rolling process, such as high friction value and non-circular contact arc, Low reduction and non-negligible entry and exit elastic zones as well as central restricted deformation zone are all taken into account. The deformation of work rolls is calculated with the influence function method and arbitrary contact arc shape is permitted. The strip deformation is modeled by slab method and the entry and exit elastic deformation zones are included. The restricted deformation Bone near the neutral point is also considered. It was revealed that the new model has better accuracy than present regression model by statistical analysis with actual mill rolling data.