• 한국환경농학회지
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• 제16권3호
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• pp.227-232
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• 1997

UV-B 조사에 의한 오이의 생장 및 생리 기능에 미치는 영향을 조사하기 위하여 비료처리에 의한 오이 제1 엽의 UV-B의 영향을 조사하였다. UV-B 조사에 의한 가시장해는 처리 1주일부터 나타났으나 생장 저해 현상은 볼 수 없었다. 그러나 UV-B 조사에 의한 생장 저해 현상은 비료 첨가에 의해 나타났으며 가장 큰 저해 효과는 질소 시용에 의해 나타났다. 이 결과는 UV-B가 질소대사에 관여하고 있음을 시사한다. 따라서 질소대사에 관여하고 있는 주 효소인 질산 환원효소 활성을 조사한 결과 UV-B 조사 7일째에 비료 처리구에서 현저히 증가하는 경향을 나타냈다. 또한 UV-B 조사에 의한 엽면적의 생장감소는 세포의 신장, 분열 생장에 관여하고 있는 식물호르몬 활성에 영향을 미치는 것으로 보여 오이의 제 1엽에서의 BA 처리에 의한 사이토카이닌의 감수성을 조사했다. UV-B 조사에 의한 사이토카이닌의 감수성은 UV-B를 조사하지 않은 구에 비해 억제되었다. 이 결과에 의해 UV-B 조사가 식물 생장에 관여하고 있는 사이토카이닌의 활성을 억제시켜 엽면적의 감소가 발생된 것으로 생각되었다.

• 한국전기전자재료학회논문지
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• 제21권9호
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• pp.859-862
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• 2008

We have realized static image on organic light emitting diodes (OLEDs) using photoluminescence degradation. Ultraviolet (UV) was irradiated to the glass side of device. UV power was 350 Wand the wavelength was 365 nm. The UV irradiation gives rise to the degradation of photoluminescence. Due to the degradation, the current density-voltage curve was shifted to the higher voltage side and the luminescence was also degraded by the current and photoluminescence drop. The negative imaged films were prepared to control the transmittance of UV. The UV light was passed through the film. By this method, the film image was transferred to the device with reversed image and the static image was realized on the OLED.

• Journal of Ginseng Research
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• 제45권3호
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• pp.456-463
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• 2021

Background: Keratinocytes form a physical barrier and act as an innate immune cell in skin. Keratinocytes secrete pro-inflammatory cytokines, such as interleukin (IL)-1β, resulting from inflammasome activation when exposed to ultraviolet (UV) irradiation. Korean Red Ginseng extracts (RGE) have been well-studied as modulators of inflammasome activation in immune cells, such as macrophages. In the study, we elucidated the role of RGE on the UV-mediated inflammasome activation in keratinocytes compared with that in macrophages. Methods: Human skin keratinocyte cells (HaCaT), human epidermal keratinocytes (HEK), human monocyte-like cells (THP-1), and mouse macrophages were treated with RGE or a saponin fraction (SF) or non-saponin fraction (NS) of RGE before and after UV irradiation. The secretion levels of IL-1β, as an indicator of inflammasome activation, were analyzed. Results: The treatment of RGE or SF in macrophages after UV irradiation inhibited IL-1β secretion, but similar treatment in HaCaT cells did not. However, the treatment of RGE or SF in HaCaT cells in the presence of poly I:C, a toll-like receptor (TLR) 3 ligand, before UV exposure elicited the inhibition of the IL-1β secretion. The inhibition was caused by the disruption by RGE or SF of the TLR mediating up-regulation of the pro-IL-1β and NLRP3 genes during the priming step. Conclusion: RGE and its saponins inhibit IL-1β secretion in response to UV exposure in both keratinocytes and macrophages. In particular, RGE treatment interrupted only the priming step in keratinocytes, although it did attenuate both the priming and activation steps in macrophages.

• 대한의생명과학회지
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• 제22권1호
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• pp.18-23
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• 2016

Ultraviolet (UV) irradiation induces cellular damage. A variety of cellular responses for repairing cellular damage including DNA damage occur after UV irradiation. During the repair processes, expression and activation of various molecules are regulated depending on the types of cellular damage. Parkin is an E3 ligase and act as a tumor suppressor. Recently, it has been reported that Parkin is involved in the DNA repair process. In the current study, we investigated whether UVB irradiation influences expression of Parkin. Parkin expression transiently decreased after UVB irradiation both at the mRNA and protein levels, but returned to normal levels thereafter. Taken together with cell viability data, Parkin expression is down-regulated during UVB-induced suppression of cell growth and is increased again in accordance with recovery of UVB-induced cell growth inhibition. However, Parkin overexpression or knockdown did not influence UVB-induced cell growth inhibition and recovery. We propose that Parkin could be a useful molecular marker for evaluating conditions of cells after UVB irradiation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1261-1263
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• 1998

In this paper, we obtained that the monodomain alignment of nematic liquid crystal (NLC) increases with increasing irradiation time with linearly polarized ultraviolet (LPUV) light irradiation on polyimide (PI) surfaces. It was found that the monodomain alignment of NLC is obtained in a cell with normally LPUV light irradiated on PI surface at 30 min. and then oblique LPUV is secondly irradiated on PI surfaces rotated by $90^{\circ}$. The pretilt angle of NLC is generated about $2.5^{\circ}$ with oblique angle of $60^{\circ}$ and then decreased with increasing the oblique angle of IN light irradiation. It is considered that the pretilt angle of NLC is attributed to the photo-depolymerization of polymer with the oblique angle of UV light. The voltage-transmittance and response time characteristics of photo-aligned twisted nematic (TN)-LCD with UV light irradiation time of 60 min. were almost same in comparison with rubbing treated TN-LCD.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.109-112
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• 1998

In this paper, we studied on electro-optical (EO) characteristics of photo-aligned twisted nematic (TN)-LCD. We obtained that uniform LC alignment in TN-LCD with linearly polarized ultraviolet (LPUV) light irradiation on polyimide (PI) surface increases according to increasing irradiation time for 10 to 60 min. The voltage-transmittance and response time characteristics of photo-aligned TN-LCD with UV light irradiation time of 60 min were almost same in comparison with conventional TN-LCD were observed. From the results, we suggest that photo-aligned TN-LCD with LPUV light irradiation on PI surface is useful in applying LCD as for rubbing-free treatment method.

• 동의생리병리학회지
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• 제22권2호
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• pp.346-349
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• 2008

To investigate whether aqueous extract from Aconitum koreanum (AEAK) effects in the process of melanin synthesis, the expression of tyrosinase-related proteins (TRPs) by immunohistochemical methods were performed in ultraviolet B (UVB) irradiated skin of guinea pig. The irradiation of UVB (60 mJ/day) was performed for 3 days and treated with AEAK for 15 days. About the color evaluation, the visual scores of UV B irradiated guinea pig with AEAK treatment were slightly lower than those in the UV B alone irradiated ones. At day 15 after UVB exposure, immunohistochemical analysis for TRPs expression were performed. The intensive expression of tyrosinase was mainly observed over epidermis with skin appendage and in the cells of dermis. Slight increase of these reaction was induced in response to UVB in the spinous and granular layer of epidermis, but similar expression in the AEAK treated guinea pig as normal one. The TRP-1 and TRP-2 expression were not detected in the skin of normal guinea pig. But intensive expression for TRP-1 and TRP-2, especially TRP-2, induced by UV B irradiation in the cells of dermis. These expressions were decreased in the AEAK treated guniea pig. Collectively, these results suggest that AEAK has a potential to inhibit synthesis through regulation of TRPs expression in the skin of guinea pig, but better understanding the function of AEAK, more research should be done in the effects of AEAK on the function of TRPs in melanogesis.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.116-119
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• 1997

We investigated new type non-robbing liquid crystal (LC) alignment techniques in the cell with slanted non-polarized ultraviolet (UV) irradiation on polyimide (Pl) film. It is shown that the uniform alignment for nematic (N) LC is obtained by using slanted non-polarized UV irradiation on Pl surface. We successfully obtained that the pretilt ang1e of NLC is generated about 3 degree in the LC cells by using slanted non-polarized UV irradiation with 70 degree on Pl surface. We consider that the pretilt angle generation for NLC is attributed to interaction between the LC molecular and the PI surface. We conclude that the uniform LC alignment is attributed to anisotropic dispersion force effect due to photo depolymerization of polymer on Pl surface.

• 한국물환경학회지
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• 제28권1호
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• pp.57-62
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• 2012

In this study, the inactivation efficiency of Mycobacterium marinum was evaluated in buffered water (pH 7) using a low pressure ultraviolet (LP-UV) lamp, ultrasonic (US), and UV/US sequential processes. In the UV alone process, 3 log inactivation of the M. marinum was achieved with a UV dose of $120mJ/cm^2$. However, a tailing phase was later observed because M. marinum has a high tendency for cell aggregation. Even though the M. marinum was not inactivated in the US alone process, the hydrophobicity decreased and turbidity increased due to the crumbling of the cell aggregation. Among the candidate processes which were UV alone, US-UV sequential process and UV-US-UV sequential process, the US-UV sequential process showed the highest synergistic effects for M. marinum inactivation. Consequently, US is a very useful process as a UV irradiation pre-treatment to inactivate M. marinum in water.

• 한국인쇄학회지
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• 제16권3호
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• pp.29-41
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• 1998

The ultraviolet(UV)-curable materials wildly have been used as a ink and coating materials. A according to measure UV polymerization phase separation of acryl groups 2,3,4-functional monomer, a few experiments were performed gel fraction, dynamic viscosity of alkyd resin blend system. Dependence of photoiniator concentration and various monomer, alkyd resin content investigated structural changes of films cured by UV irradiation. Curing rate measured UV irradiation under $25^{\circ}C$, cell gap 7cm and film thickness 100${\mu}{\textrm}{m}$. In results, it was through that the viscoelastic properties of films cured with increasing the ratios of monomer/alkydresin contents are network polymer in properties such as viscoelasticity.