• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.225-237
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• 1996

The cultural characteristics of fruit bodies formation in the two selected strains(brown and yellow strain) of winter mushroom collected in Korea were investigated. The effects of various environmental conditions and physicochemical pretreatments were evaluated by the character of fruit bodies. There was no differences between two strains in non-selectivity of media, optimum temperature($11^{\circ}C{\sim}15^{\circ}C$), relative humidity(90%), and illumination(60 lux). In the application of alternated temperature (the best condition : $5^{\circ}C{\cdot}10^{\circ}C$ and $5^{\circ}C{\cdot}15^{\circ}C$), ultraviolet ray(30~50 seconds), electricity(5 seconds), thiamine hydrochloride(0.05~0.1%), urea, and IAA as a pretreatments, there was no differences between two strains. The brown strain had larger pileus and longer stipes than these of the yellow strain, while the yellow strain yielded more weight and number of the fruit body formation than the brown strain.

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.1-6
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• 2005

In this study we assessed the influences of ultraviolet (UV) light B radiation on epidermal cells by apoptotic sunburn cell (SBC) and the effect of green tea treatment on the inhibition of SBC formation in SKH1-hr mouse. The extent of changes following $200mJ/cm^2$ (0.5 mW/sec) was studied at 0, 3, 6, 12, 18, 24, 30 or 36 hours after exposure. SBCs were recognized by 3 hours after irradiation. There was tendency to increase from 3 hours to 24 hours and decrease from then to 36 hours after irradiation. The mice that received 0, 25, 50, 100, 200, 400 or $800mJ/cm^2$ of UVB were examined 24 hours after irradiation. The SBCs were induced as the radiation dose increases from 0 to $200mJ/cm^2$. A further increase of radiation dose has little further effect. The frequency of UVB ($200mJ/cm^2$)-induced SBC formation was reduced by intraperitoneal injection of green tea extract (p<0.01).

• Polymer(Korea)
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• v.38 no.3
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• pp.397-405
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• 2014

To manufacture of high-performance semi-structural double-sided adhesive tape, 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AAC) were used, and the syrup was prepared by UV irradiation in this study. The effects of the thickness, various inorganic filler contents, and filler types on the semi-structural properties of acrylic double-sided adhesive tape were investigated. The peel strength increased with increasing thickness and wetting time. In case of the thin thickness (under $250{\mu}m$) with decreasing true density of inorganic filler, the peel strength increased with increasing wetting time. The initial peel strength showed a higher value at a big size of inorganic filler, and the filler's size in adhesive tapes was confirmed by SEM images. The peel strength and dynamic shear strength increased as a proportional relationship with various inorganic fillers and contents, and these inorganic fillers in $0.1{\mu}m$ thickness indicated more effect on the dynamic shear strength of double-sided adhesive tape. From these results the thin acrylic double-sided adhesive tape determined to be use for applications as a high-performance semi-structural.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.105-112
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• 2015

Resveratrol is a natural polyphenol. It protects skin from skin injury, ultraviolet radiation and pathogenic attack. This study is to find the optimum condition for the preparation of ethosome loading amount of resveratrol in ethosome. Ethosomes were prepared by modified hydrated liquid crystal method. Investigation of factors affecting the entrapment efficiency and particle size of ethosomes was carried out. The particle size of ethosome were measured by particle analyzer. The loading efficiency of resveratrol in ethosome was measured by HPLC. The particle sizes were 111.2 ~ 112.8 nm and the loading efficiency of resveratrol was 81.25 ~ 88.75%. The optimum conditions for the preparation of ethosome was obtained from of lecithin : resveratrol : cholesterol : ethanol at a weight ratio of 2.0 : 0.08 : 0.05 : 20.0.

• Journal of Ginseng Research
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• v.30 no.4
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• pp.188-193
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• 2006

We induced the activation of melanocytes in the epidermis of C57BL/6 mice by ultraviolet B (UVB) irradiation and observed the effect of red ginseng (RG) on the formation, and decrease of UVB-induced epidermal mel-anocytes. C57BL/6 mice were irradiated by UVB $80mJ/cm^2$ (0.5 mW/sec) daily for 7 days, and RG was intraperitoneally or topically applied pre- or post-irradiation. For the estimation of change of epidermal melanocytes, light microscopic observation with dihydroxyphenylalanine (DOPA) stain was performed. Split epidermal sheets prepared from the ear of untreated mice exhibited 11-16 $melanocytes/mm^2$, and one week after UV irradiation, the applied areas show an increased number of strongly DOPA-positive melanocytes with stout dendrites. But intraperitoneal or topical treatment with RG before each irradiation interrupted UVB-induced pigmentation and resulted in a marked reduction in the number of epidermal melanocytes as compared to radiation control skin. The number and size of DOPA-positive epidermal mel-anocytes were also significantly decreased in intraperitoneally injected or topically applicated group after irradiation with RG at 3rd and 6th weeks after irradiation. The present study suggests the RG as inhibitor of UVB-induced pigmentation and depigmenting agent.

• The Korean Journal of Zoology
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• v.21 no.2
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• pp.43-58
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• 1978

Heavy metal treatment on the fertilized frog eggs before the first cleavage results in a quantitative alteration in the number of PGCs. The formation of PGCs is inhibited by a limited range of heavy metal during the early embryonic development. Total doses of lead above 70ppm and doses of cadmium above 4ppm result in a partial reduction of germ cells at the mitotically dormant stage. After this stage the germ cell number increases almost at the same rate as the untreated control tadpoles. In contrast, on mercury treated eggs, total doses above 0.8ppm cause more damage to germ cell formation. Their proliferation rate thereafter seems to be lower compared with the others. These facts seem to suggest that the heavy metal treatment on frog eggs prior to the first cleavage division is not highly effective in the complete elimination of PGCs in constrast with UV irradiation, even though cytolysis of the tissue occurs in the tadpoles.

• Journal of Conservation Science
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• v.25 no.1
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• pp.77-86
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• 2009

The physical properties of the epoxy resins were studied with an addition of filler content and the application of artificial weathering test. When talc as a filler was added to the epoxy resin (L-30), the water resistance seemed to be increased because of the results of the reducing of water absorption rate and the increasing of contact angle. Although the adhesive strength of epoxy resins was not affected by the increasing amount of talc, its compressive strength was reduced. The physical properties of the epoxy resins had different trends according to the site environments. The artificial weathering test with the change of temperature and humidity showed that the changes of water absorption rate and colour differences of the epoxy resins containing talc were lower than the pure epoxy resin itself. However, the contact angle was higher. The artificial weathering test with ultraviolet irradiations showed the opposite result; the damage of epoxy resins was increased with the increasing of talc content. These mean the site environment of the stone monuments should be considered to determine the content of talc added to increase the durability of epoxy resin.

• Applied Microscopy
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• v.28 no.2
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• pp.127-137
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• 1998

This study was observed of the skin that changed after irradiation of the ultraviolet A. All the mouse were hairless which the weight are about 25g and the ages $6\sim8$ weeks old. The mouse were divided into six groups; control, irradiated for 6 hours, 3 days, 7 days, 14 days, 21 days and 28 days. Each group was irradiated with ultraviolet that is $320nm\sim366nm$ of wavelengths. After irradiated, the skin was observed with the electron microscope and the light microscope. The results are as follow: 1) Light microscopy With following irradiation, the epidermis was not changed to most groups but at the 28 days group was thickened and deposit the melanocyte. The elastic fibers within the epidermis were thickened and twisted with following irradiation. 2) Eelectron microscopy The elastic fibers were slightly clumped at 6 hours group, mildly increased and partly aggregated in the 3 days group, branched and tangled at 7 days group, irregulated and electron density at 14 days group, sightly thickened and twisted at 21 days group, and randomly arranged, shortened, twisted, and electron density at 28 days group.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.2
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• pp.13-32
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• 2011

Objectives: This study was performed to elucidate the effects of Danchisoyo-san (DS) on cell damage and gene expression in UVB-exposed dermal fibroblast. Methods: To demonstrate the inhibitory effects of DS on aging of the skin, we used human dermal fibroblast(F6) and UVB light(30 mJ/$cm^2$) was used to damage to dermal fibroblast. We measured the nitrite production, LDH release, and gene expression in UVB-irradiated dermal fibroblast to elucidate the actionmechanism of DS. Also, we evaluated the amount of increased PICP, TIMP-1 in dermal fibroblast. PICP, TIMP-1 concentration was measured using EIA kit, and gene expression (MMP-1, procollagen, c-fos, c-jun, NF-kB, Bcl-2, Bcl-xL, iNOS) were determined using real-time PCR. Results: 1. DS inhibited LDH-release, nitrite production in UVB-irradiated dermal fibroblast. 2. DS suppressed the gene expression of MMP-1 in UVB-irradiated dermal fibroblast. 3. DS increased the gene expression of procollagen in UVB-iradiated dermal fibroblast. 4. DS suppressed the gene expression of c-jun, c-fos, NF-kB, iNOS in UVBirradiated dermal fibroblast. 5. DS increased the gene expression of Bcl-2 in UVB-iradiated dermal fibroblast. 6. DS increased the cell proliferation of dermal fibroblast. Conclusions: From the results, we concluded DS increases the cell proliferation and collagen synthesis in dermal fibroblast. So we suggest that DS has the antiwrinkle effects.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.275-281
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• 2014

In this study, accelerated weathering test was performed with wood, a major material for wooden cultural building. In order to evaluate the deterioration of wood, ultrasonic transmission times were measured to evaluate dynamic modulus of elasticity (MOE), which was verified by determining static MOE using three-point bending test. Ultrasonic transmission time was decreased with an increase in the weathering time levels (0, 500, 1000 hours) while it increased in 1500 and 2000 hours. Distribution of dynamic and static MOE was similar to that of the ultrasonic transmission time measurements. The results mean that the measurement of ultrasonic transmission time was very effective to evaluate MOE of wooden cultural buildings for their preservation and management. This method could be utilized to assess wooden cultural buildings as a way of preserving them in a scientific manner.