• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.5
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• pp.646-653
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• 1998

Because there is a great concern' today about the damaging effect of chronic exposure to sunlight the use of sunscreen providing the photoprotection effect against ultraviolet (UV) was widely increased. As a result of common use of level of photosynthetic Vit. D3 in human skin decreased these days. In our experiment the animals covered with fabrics with 50% (fabric B) and 100% (fabric A) protection rate against ultraviolet B (UVB) were used to measure serum 25(OH)D3, ALP, total clacium and phosphorus. Vitamin D deficiency diet group had no effect on concentration of serum phosphorus. But the concentrations of serum 25(OH)D9 and total calcium were more decreased in vitamin D deficiency diet rats than in normal diet rats. Alkaline phosphatase activity in sunlight irradiated groups covered with 50% (fabric B) and 100% (fabric A) WB protection fabrics was more significantly decreased than vitamin D deficiency diet group. In conclusion, sunlight irradiateted groups were compared to effective to protect born disease due to the Vit. D deficeincy group.

• Bulletin of the Korean Space Science Society
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• 1992.10a
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• pp.14-14
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• 1992

The IUE archival spectra of VV Cephei were collected to investigate the eclipse nature in the ultraviolet. The temperature of the B star has been determined, as approximately30,OOOK, based en the flux distributions durstributions during egress, Light curves of VV Cephei were reduced from the spectrophotometry of the IUE archival spectra. Three light curves at the center wavelengths of 2350A,2550A and :!850A have been analyzed by the modified Wilson and Oevinney light curve program. the radii of the B star and M star were deduced to 0.05 and 0.22 of uint separation, respectively. The UV light curves show anevidence that the light was attenuated by the highly opaque atmosphere of the M star

• Journal of Astronomy and Space Sciences
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• v.9 no.1
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• pp.111-119
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• 1992

The IUE archival spectra of VV Cephei were collected to investigate the eclipse nature in the ultraviolet. The temperature of the B star has been determined, as approximately 30000K, based on the flux distributions during egress. Light curves of VV Cephei were reduced from the spectrophotometry of the IUE archival spectra. Three light curves at the center wavelengths of 2350 ${\AA}$, 2550 ${\AA}$ and 2850 ${\AA}$ have been analyzed by the modified Wilson and Devinney light curve program. The radii of the B star and M star were deduced to 0.05 and 0.22 of unit separation, respectively. The UV light curves show an evidence that the light was attenuated by the highly opaque atmosphere of the M star.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.794-798
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• 2003

The reactive oxygen species (or free radicals) generated by ultraviolet radiation cause damage on cellular components and pigment of skin. The aim of this study was to investigate the skin-whitenig effect of Okyong-san. Inhibitory effects of okyong-san extracts on melanin synthesis were studied. Namely, UV-absorbing ability, free radical scavenging activity and tyrosinase inhibitory activity of okyong-san extracts were investigated. As a result, the extracts of okyong-san were found to inhibit the activity of tyrosinase and they showed an absorbance in the UV-B region and UV-C region. We also observed that extracts of okyong-san had free radical scavenging activity.

• Atmosphere
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• v.21 no.1
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• pp.123-130
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• 2011

In this study, we have analyzed the radiative characteristics of erythemal ultraviolet-B (EUV-B from 1999 to 2005) over the Korean Peninsula. EUV-B measured at Gangneung, Anmyondo, Mokpo, and Gosan represents the measurements from clean areas and that at Seoul represents from a polluted area. The magnitudes of EUV-B increase in proportion to the latitudinal decrease. Monthly mean variation of EUV-B at noon shows the maximum value of $158.5mWm^{-2}$ in August and the minimum value of $36.4mWm^{-2}$ in December in the clean areas. Seasonal mean diurnal variation of EUV-B shows a peak around noon (12:00 ~ 13:00 hr) and its intensity varies along with a season in order of summer > spring > fall > winter. The maximum value of $56.4mWm^{-2}$ in summer is three times higher than that in winter ($14.3mWm^{-2}$). The value of EUV-B in the polluted area is lower than that in the clean areas, resulting from the effects of the blocking, reflection, and scattering of EUV-B due to high concentrations of PM10. UV-B is an essential element to synthesize vitamin D in human body. 200 IU(International Unite) of vitamin D can be formed by an exposure of 6-10% of body surface area to 0.5 MED(Minimal Erythemal Dose). In order to form vitamin D, the calculated exposure times to EUV-B are 15 min. in spring, 12 min. in summer, 18 min. in fall, and 37 min. in winter for the clean areas and 16, 16, 24, and 37 min. for the polluted area.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.396-400
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• 2000

For an attempt to develop safe materials protecting solar ultraviolet (UV)-induced skin damage, plant extracts were evaluated for their inhibitory activities of free radical generation and arachidonic acid/metabolites release from UVB-irradiated normal human keratinocytes. From the results of these screening procedures, the ethanol extract of the flowers of Prunus persica (Ku-35) was selected for further study. It was found that Ku-35 (100-1,000 ${u}g/m\ell$) inhibited the amount of $^{14}C$-arachidonic acid/metabolites release from UVB-irradiated keratinocytes. It was also demonstrated that Ku-35 possessed the protective activity against UV-induced cytotoxicity of keratinocytes and fibroblasts. In addition, Ku-35 was revealed to protect UVB-induced erythema formation using guinea pigs in preliminary in vivo study. All these results indicate that the flowers of P. persica extract may be beneficial for protecting UV-induced skin damage when topically applied.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.780-803
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• 2003

Exposure of skin cells, particularly keratinocytes to various nuclear factor-kappaB ($\textrm{NF}_{-{\kappa}}\textrm{B}$) activators [e.g. tumor necrosis factor-$\alpha$, interleukin-1, lipopolysaccharides, and ultraviolet light] leads to phosphorylation and degradation of the inhibitory protein, $\textrm{I}_{{\kappa}}\textrm{B}$. Liberated $\textrm{NF}_{-{\kappa}}\textrm{B}$ is translocated into the nucleus where it can change or alter expression of target genes, resulting in the secretion of extracellular signaling molecules including melanotrophic factors affecting melanocyte. In order to demonstrate the possible role of $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation on the synthesis of melanotrophic factors from the keratinocytes, the activities of $\textrm{NF}_{-{\kappa}}\textrm{B}$ induced by melanogenic inhibitors (MIs) were determined in human HaCaT keratinocytes transfected with $\textrm{pNF}_{-{\kappa}}\textrm{B}$-SEAP-NPT plasmid. Transfectant cells released the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the $\textrm{NF}_{-{\kappa}}\textrm{B}$ activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selection marker for geneticin resistance. MIs such as niacinamide, kojic acid, hydroquinone, resorcinol, arbutin, and glycolic acid were preincubated with transfectant HaCaT cells for 3 h and then ultraviolet B (UVB) was irradiated. $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation was measured with the SEAP reporter gene assay using a fluorescence detection method. Of the Mis tested, kojic acid ($IC_{50}$/ = 60 $\mu$M) was found to be the most potent inhibitor of UVB-upregulating $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation in transfectant HaCaT cells, which is followed by niacinamide ($IC_{50}$/= 540 $\mu$M). Pretreatment of the transfectant HaCaT cells with the Mis, especially kojic acid and niacinamide, effectively lowered $\textrm{NF}_{-{\kappa}}\textrm{B}$ binding measured by electrophoretic mobility shift assay. Furthermore, these two inhibitors remarkably reduced the secretion level of IL-6, one of melanotrophic factors, triggered by UV-radiation of the HaCaT cells. These observations suggest that Mis working at the in vivo level might act partially through the modulation of the synthesis of melanotrophic factors in keratinocyte.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1457-1459
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• 2001

This paper deals with the change of surface Potential decay, surface resistivity, contact an91e and XPS of ultraviolet-treated PET films. From the experimental results on the surface Potential decay of UV degraded-samples, it was found that the accumulation of charge is decreased and the surface potential decay time is shortened. Also, from the result of XPS, it was found that the changes affected by the surface degradation of PET film were caused by the generation of carboxyl groups through the chain decomposition and recombination with oxygen molecules in the air.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.1
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• pp.70-82
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• 2008

Objective : The purpose of this study is to examine the effects of Baickbujasan(BB) on the skin damage and depigmentation. Method : The inhibition of tyrosinase activity, melanogenesis and cell viability in cultured B16 melanoma cells were measured. In order to test effects of reduction of melanogenesis, B16 F-10 mouse melanoma stem line was employed to extract melanin from cultured cell, where BB was added or not, and was dissolved in alkali for colorimetric analysis. Also, in order to test skin alteration in C57BL/6 after UV irradiation, the animals were grouped into a UV urradiation group and UV irradiation after BB application group. Dopa oxidase tissue staining was excuted to invesitage the change in the distribution of active melanin cell. The distribution of active melanin cell in inner skin of iNOS after damage from UVB irradiation and the manifestation condition of P53 which takes part in natural death of keratinocyte were examined. Result : The results indicate that BB has significant effects on tyrosinase activity, and melanogenesis in vivo test. BB seems to reduce C57BL/6, external dermatological damage, for instance, erythematous papule, eczema, loss of keratinocyte, reduction in pus, and relieves dermatological damages. Conclusion : BB can be applied externally for UV protection and depigmentation.