• Title/Summary/Keyword: Ultra-violet rays

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The Processed Radish Extract Melanogenesis in Humans and Induces Anti-Photoaging Effects in Ultraviolet B-Induced Hairless Mouse Model

  • Kim, Hyun-Kyoung
    • International Journal of Advanced Culture Technology
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    • v.7 no.4
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    • pp.125-136
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    • 2019
  • The radish skin and radish greens are an edible part of the radish. But they are removed before eating the radish and used as a byproduct or an animal feed material because of their tough and rough texture. Melanin is a pigment that gives colour to our skin. But increased production of melanin can turn into benign or malignant tumours. These days due to global warming, the amount of Ultra violet (UVB) rays has been extensively increased with sunlight. Due to this, a phenomenon called exogenous photo aging is widely observed for all skin colour and types. As a result of this phenomenon, a set of enzymes called matrix metalloproteinases (MMP's) that serves as degradation enzymes for extracellular matrix proteins mainly collagen is increased, causing depletion in collagen and resulting in early wrinkles formation. Therefore in our study we used the murine melanoma cell line B16/F10 to study the melanogenesis inhibition by Heated radish extract (HRE) in vitro and we used HRM-2 hair less mice exposed to artificial UVB for checking the efficacy of Heated radish extract in vivo. Furthermore, we prepared a 3% Heated radish extract (HRE) cream and checked its effects on human skin. Our results have clearly demonstrated that Heated radish extract (HRE) have potently suppressed the tyrosinase activity and melanin production in B16/F10 cells. It had also reduced the expression of components involved in melanin production pathway both transcriptionally and transitionally. In in vivo studies, HRE had potently suppressed the expression of MMP's and reduced the wrinkle formation and inhibited collagen degradation. Moreover, on human skin, ginseng cream increased the resilience, skin moisture and enhanced the skin tone. Therefore in light of these findings, we conclude that HRE is an excellent skin whitening and antiaging product.

A Study on Paving Technique using Polymer Epoxy Resin Materials (고분자 에폭시 수지혼합물을 이용한 포장기술 연구)

  • Oh, Seung Hwoon;Kim, Nak Seok;Kim, Wan Sang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.2D
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    • pp.209-216
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    • 2009
  • This study was conducted to develop a thin paving technique using polymer epoxy resin materials which is considered as a durable pavement materials. The mechanical performance characteristics of the polymer epoxy resin materials were also evaluated to confirm the validity as a pavement materials. To estimate the performance properties of the materials, bending tests and bonding tests were performed using freeze-thaw and ultra-violet rays to accelerate the aging of materials. In addition, HYUNStay, a commercial structural analysis program for cable-stayed bridges, was used to compare the effect of paving materials between the polymer epoxy resin materials and the conventional ones on the reduction of cable tension and on the stability of the main tower. According to the test results, it is noted that the thin paving technique using polymer epoxy resin materials can improve the performance and durability of pavement compared to the conventional one.

Evaluation of Bond Strength in FRP Hybrid Bar Affected by Freezing/thawing Test and UV Rays (동결융해 및 UV 폭로시험을 거친 FRP Hybrid Bar의 인발거동특성 평가)

  • Park, Jae-Sung;Yoon, Yong-Sik;Park, Ki-Tae;Kwon, Sung-Jun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.1
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    • pp.53-58
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    • 2017
  • FRP Hybrid Bar, composed of an embedded steel and the coated composites with epoxy and glass fiber, is an effective construction material with tension-hardening performance and lightweight. The epoxy exposed to UV(Ultra Violet Rays) and FT(Freezing and Thawing) action easily shows a surface deterioration, which can cause degradation of bonding strength between inside-steel and outside-concrete. In the present work, surface inspection for 3 different samples of normal steel, FRP Hybrid Bar before UV, and FRP Hybrid Bar after UV test was performed, then concrete samples with 3 reinforcement types were prepared for accelerated FT test. Through visual inspection on 3 typed reinforcement, no significant deterioration like chalking was evaluated. The results from FT test to 120 and 180 cycles showed FRP Hybrid Bar exposed to UV test has higher bonding strength than normal steel by 106.3% due to enlarged bond area by silica coating. The 3 cases showed a similar bond strength tendency with increasing FT cycles, however a relatively big deviations of bond strength were evaluated in FRP Hybrid Bar after UV test due to loss of silica coating.

Study on the Sun Protection Factor(SPF) Test Method for Sun Product Water Resistance (내수성 자외선 차단제의 자외선 차단지수 평가방법 연구)

  • Mun, Kyoung-Jin;Kim, So-Un;Mun, Ju-Hee;Kim, Soo-Jin;Kim, A-Young;Moon, Tae-Kee;Kim, Nam-Soo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.1
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    • pp.63-66
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    • 2008
  • Sunscreen is usually used by people when they are at the beach or outdoor swimming pools. Since the existing methods of and standards for measuring the effects of blocking ultra violet rays do not employ water resistance test methods, the establishment of a water resistance SPF test method is required. In this study, to standardize the SPF evaluation methods for a water resistant sunscreen, proposed measurement methods in this study were compared with those of foreign countries. Selected water resistance SPF experiments confirmed the product's suitability and a verification test was then conducted by establishing the variables of water resistance SPF measurement methods. In the comparative experiment on water resistance SPF given a water temperature of $23{\sim}32$ degrees centigrade showed that temperature did not have any statistically significant effect on water resistance SPF. The changing water flow also did not have any statistically significant effect on the water resistance SPF. Therefore, continuous 20 min water circulation is deemed appropriate as an alternative to the subject's usual activity.

UV Absorption of Nano-thick $TiO_2$ Prepared Using an ALD (ALD 방법으로 제조된 나노급 $TiO_2$에 의한 자외선 차단효과 연구)

  • Han, Jeung-Jo;Song, Oh-Sung;Ryu, Ji-Ho;Yoon, Ki-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.4
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    • pp.726-732
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    • 2007
  • We fabricated UV absorption functional $10{\sim}50nm-TiO_{2-x}/quartz$ structures layer using ALD (atomic layer deposition) method. We deposited $10nm-TiO_{2-x}$ layer on quartz substrate using ALD, and film thickness was determined by an ellipsometer. The others specimen thickness was controlled by ALD time lineally. We characterized controlling phase UV and visible optical property using an X-ray difractometer, a UV-VIS-IR spectrometer and a digital camera. $ALD-TiO_{2-x}$ layers were non-stoichiometric $TiO_{2-x}$ form and amorphous phases comparing with bulk $TiO_2$. While the conventional bulk $TiO_2$ had band gap of $3.0{\sim}3.2eV$ resulting in absorption edges at 380 nm and 415 nm, $ALD-TiO_{2-x}$ layers showed absorption edges at 197 nm and 250 nm. Therefore, our nano-thick $ALD-TiO_{2-x}$ was able to absorb shorter UV region and showed excellent transmittance in visible region. Our result implies that our newly proposed nano-thick $TiO_{2-x}$ using ALD process may improve transmittance in visible rays and be able to absorb shorter UV light effectively.

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