• Title/Summary/Keyword: Sun: UV radiation

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Study on Photo-aging Inhibition Effect of Microalgae-derived Oil for Cosmetic Material Development (화장품 소재 개발을 위한 미세조류 유래 오일의 광노화 억제 효과 연구)

  • Park, Eun-Kyung;Park, Sang-Hee;Yoon, Sang-A;Kim, You Sun;Lee, Woo-Ram;Kim, Woo-Jung
    • Journal of Marine Bioscience and Biotechnology
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    • v.10 no.2
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    • pp.83-90
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    • 2018
  • Ultraviolet (UV) radiation causes inflammation and matrix metalloproteinase (MMP) over-expression and extra cellular matrix depletion, leading to skin photo-aging such as wrinkle formation, dryness, and sagging. In this study, we demonstrated that pretreatment with the hexane extract of microalgae protects UVB mediated cell damages. The results of clinical study showed that Microalgal Oil treated group reduced wrinkle and improve elasticity. All these results suggest Microalgal Oil may be useful as new photo-aging cosmetics for protection against UV induced activity.

Inhibitory mechanism of ginsenoside Rh3 on granulocyte-macrophage colony-stimulating factor expression in UV-B-irradiated murine SP-1 keratinocytes

  • Park, Young Sun;Lee, Ji Eun;Park, Jong Il;Myung, Cheol hwan;Lim, Young-Ho;Park, Chae Kyu;Hwang, Jae Sung
    • Journal of Ginseng Research
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    • v.44 no.2
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    • pp.274-281
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    • 2020
  • Background: Ultraviolet (UV) goes through the epidermis and promotes release of inflammatory cytokines in keratinocytes. Granulocyte-macrophage colony-stimulating factor (GM-CSF), one of the keratinocyte-derived cytokines, regulates proliferation and differentiation of melanocytes. Extracellular signal-regulated kinase (ERK1/2) and protein kinase C (PKC) signaling pathways regulate expression of GM-CSF. Based on these results, we found that ginsenoside Rh3 prevented GM-CSF production and release in UV-B-exposed SP-1 keratinocytes and that this inhibitory effect resulted from the reduction of PKCδ and ERK phosphorylation. Methods: We investigated the mechanism by which ginsenoside Rh3 from Panax ginseng inhibited GM-CSF release from UV-B-irradiated keratinocytes. Results: Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) or UV-B induced release of GM-CSF in the SP-1 keratinocytes. To elucidate whether the change in GM-CSF expression could be related to PKC signaling, the cells were pretreated with H7, an inhibitor of PKC, and irradiated with UV-B. GM-CSF was decreased by H7 in a dose-dependent manner. When we analyzed which ginsenosides repressed GM-CSF expression among 15 ginsenosides, ginsenoside Rh3 showed the largest decline to 40% of GM-CSF expression in enzyme-linked immunosorbent assay. Western blot analysis showed that TPA enhanced the phosphorylation of PKCδ and ERK in the keratinocytes. When we examined the effect of ginsenoside Rh3, we identified that ginsenoside Rh3 inhibited the TPA-induced phosphorylation levels of PKCδ and ERK. Conclusion: In summary, we found that ginsenoside Rh3 impeded UV-B-induced GM-CSF production through repression of PKCδ and ERK phosphorylation in SP-1 keratinocytes.

Light Fastness of Silk Fabric dyed with Safflower and Amur Cork Tree extract for Combination dyeing (홍화와 황벽의 혼합염색 견직물의 광퇴색)

  • Jung Sun-young;Jang Jeong-dae
    • Textile Coloration and Finishing
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    • v.16 no.5
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    • pp.8-18
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    • 2004
  • In order to study on the color change of silk dyed with natural colorant due to light fading, and find out the effect of combination dyeing, colorant extracts of safflower red, safflower yellow and amur cork tree were used, either singly or in combination. In combination dyeing, safflower yellow or amur cork tree dyeing process was added on the top of the silk fabric was dyed with safflower red. Color change and light fastness were investigated by $L^*,\; a^*,\; b^*$ H, V/C, and Color difference. Brightness of silk fabric dyed with safflower red and safflower yellow increased gradually with increasing the radiation time of UV light, but amur cork tree was decreased and turned to dull. Color difference of dyed with Amur cork tree showed higher than the others. Combination dyeing of safflower red and amur cork tree provided better light fastness than the one of safflower red and safflower yellow.

Remote Measurement of Ultraviolet Reflections for the Guidelines for Leisure Tourism Activities on the Adjacent Coast of the Demilitarized Zone Peace Life Belt (비무장지대 평화생명벨트 인접해안에서의 레저관광활동 가이드라인을 위한 자외선 반사량 원격측정)

  • Uh, Je-Sun;Choi, chul-Jae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.3
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    • pp.499-506
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    • 2022
  • With the construction of the northern line of the East Sea in 2021, expectations for peaceful use of the Demilitarized Zone (DMZ) are rising. Accordingly, it is necessary to prepare for leisure tourism activities at nearby beaches using the Demilitarized Zone as a security ecological tourism. However, despite the increase in the amount of ultraviolet rays on the surface due to the destruction of the ozone layer, there are no guidelines for UV exposure. In this paper, the amount of ultraviolet reflection on the coast adjacent to the DMZ using remote exploration was measured and analyzed. It is hoped that the presented results will be used as basic data to prepare UV guidelines for leisure tourism activities in nearby areas.

Effects of Ultraviolet Radiation on the Skin (자외선에 의한 피부반응)

  • Youn, Jail-Il
    • Journal of Radiation Protection and Research
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    • v.20 no.3
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    • pp.181-186
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    • 1995
  • UV irradiation causes a variety of biologic effects on the skin. These effects can be devided to acute reactuons and chronic reacxtions by duration of UV irradiation. Acute reactions are erythema reaction, pigment reactions and changes in epidermal thickness. Among them erythema reaction is most common and conspicuous acute effects of the skin. Upon exposure to sun or artificial UV soures, a faint redness response of skin may begin. Larger exposure causes sunburn reaction which is exaggerated erythema reactionassociated with pain, swelling, vesicle and dulla. Extent and time course of erythema reaction depend upon several factors including wavelength and dose of UVR, skin conditions likeas skin type, site, color, temperature, humidity and environmental factors. Evaluation of erythema erythema induced by UV irradiation is difficult to quantify. Degree of redness of skin are usually estimated by subjective visual evaluation. The lowest exposure dose required to protuce erythema is called minimal erythema dose (mod). Repeated exposures of UVR result in photaging skin. In this condition we can see wrinkling, skin atrophy, dilated blood vessels and keratoses. In sensitive persons photocarcinogenesis is can Be developed on exposed area of skin. Recently skin canser is increasing now in our country. An effective public education and photopreventive method must be developed.

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DEVELOPMENT OF A TOY INTERFEROMETER FOR EDUCATION AND OBSERVATION OF SUN AT 21 cm

  • Park, Yong-Sun;Kim, Chang-Hee;Choi, Sang-In;Lee, Joo-Young;Jang, Woo-Min;Kim, Woo-Yeon;Jeong, Dae-Heon
    • Journal of The Korean Astronomical Society
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    • v.41 no.3
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    • pp.77-81
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    • 2008
  • As a continuation of a previous work by Park et al. (2006), we have developed a two-element radio interferometer that can measure both the phase and amplitude of a visibility function. Two small radio telescopes with diameters of 2.3 m are used as before, but this time an external reference oscillator is shared by the two telescopes so that the local oscillator frequencies are identical. We do not use a hardware correlator; instead we record signals from the two telescopes onto a PC and then perform software correlation. Complex visibilities are obtained toward the sun at ${\lambda}\;=\;21\;cm$, for 24 baselines with the use of the earth rotation and positional changes of one element, where the maximum baseline length projected onto UV plane is ${\sim}\;90{\lambda}$. As expected, the visibility amplitude decreases with the baseline length, while the phase is almost constant. The image obtained by the Fourier transformation of the visibility function nicely delineates the sun, which is barely resolved due to the limited baseline length. The experiment demonstrates that this system can be used as a "toy" interferometer at least for the education of (under)graduate students.

THE SWINGS EFFECTS OF THE A-X SYSTEM AND v''= 1-0 BAND OF CO

  • KIM SANG-JOON
    • Journal of The Korean Astronomical Society
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    • v.29 no.2
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    • pp.223-243
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    • 1996
  • We have constructed a line-by-line model of the A-X system of CO in order to analyze the CO bands appearing in the UV spectra of comets. The model includes electronic, rotational, vibrational transitions, excitations by solar UV radiation, and effects of neutral and electron collisions. The major bands of the A-X system occur in the $1200 - 1800{\AA}$ range where the temporal variation of solar irradiation is significant. The solar spectrum in this spectral range shows many emission lines, which cause a significant Swings effect. We derived fluorescence efficiencies of the bands as functions of heliocentric velocity and cometocentric distance using a high resolution spectrum of the sun. We compared our model with a spectrum of comet P/Halley obtained with the IUE, and estimated that the UV Swings effects are less than 20 fluorescence efficiencies for the most bands of the A-X system. We discuss the temporal variation of solar UV irradiation and its effects on the fluorescence efficiencies. The study of the A-X system also requites knowledge of vibrational and rotational fluorescent processes in the infrared and radio regions because the majority of CO molecules in the coma is in the ground rotational states. The solar infrared spectrum near 5 microns, where the fundamental band of CO occurs, contains strong absorption lines of the fundamental band and hot bands of CO and its isotopes. We derived fluorescence efficiencies of the infrared band as functions of heliocentric velocity and cometrocentric distance. The solar absorption lines near 5 microns cause a 20 reduction of the g-factor of the fundamental band at heliocentric velocities close to 0 km/sec. We discuss the effects of neutral and electron collisions on the fluorescence efficiencies of the infrared and UV bands.

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The effect of Far-infrared on survival rate of mice (원적외선이 흰쥐의 생존율에 미치는 영향)

  • Kim, Jae-Yoon;Park, Seung-Kyu;Kim, Jin-Sang;Park, Rae-Joon
    • The Journal of Korean Physical Therapy
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    • v.13 no.3
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    • pp.561-567
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    • 2001
  • IR classified by wavelength three parts NIR, MIR. FIR. There is FIR which is radiated from healthy human body the wave length is 8-14m. The Sun's ray is composed of Infared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(60%), IR(20%), and UV(20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time, in the Industrial Revolution the Infrared and FIR had been begun to use making products. FIR with low temperature can deeply penetrate on the human body composed things without troublesome, since FIR has effectively operated on the human body at low temperature (35-40 $^{\circ}$C). In this study, we experimented in the specific temperature FlR radiation intensity. water consumption rate, feed consumption rate. survival rate and mean of weight balance with FlR radiation instrument. According to the results, the FlR radiation to the mice assisted to increase the survival rate.

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Discovery of a New Mechanism of Dust Destruction in Strong Radiation Fields and Implications

  • Hoang, Thiem;Tram, Le Ngoc;Lee, Hyseung;Ahn, Sang-hyeon
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.44.3-44.3
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    • 2019
  • Massive stars, supernovae, and kilonovae are among the most luminous radiation sources in the universe. Observations usually show near- to mid-infrared (NIR-MIR, 1-5~micron) emission excess from H II regions around young massive star clusters (YMSCs) and anomalous dust extinction and polarization towards Type Ia supernova (SNe Ia). The popular explanation for such NIR-MIR excess and unusual dust properties is the predominance of small grains (size a<0.05micron) relative to large grains (a>0.1micron) in the local environment of these strong radiation sources. The question of why small grains are predominant in these environments remains a mystery. Here we report a new mechanism of dust destruction based on centrifugal stress within extremely fast rotating grains spun-up by radiative torques, namely the RAdiative Torque Disruption (RATD) mechanism, which can resolve this question. We find that RATD can destroy large grains located within a distance of ~ 1 pc from a massive star of luminosity L~ 10^4L_sun and a supernova. This increases the abundance of small grains relative to large grains and successfully reproduces the observed NIR-MIR excess and anomalous dust extinction/polarization. We show that small grains produced by RATD can also explain the steep far-UV rise in extinction curves toward starburst and high redshift galaxies, as well as the decrease of the escape fraction of Ly-alpha photons observed from HII regions surrounding YMSCs.

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Educational Activities for Rural and Urban Students to Prevent Skin Cancer in Rio Grande do Sul, Brazil

  • Velasques, Kelle;Michels, Luana Roberta;Colome, Leticia Marques;Haas, Sandra Elisa
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1201-1207
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    • 2016
  • Background: Excessive exposure to the sun during childhood is strongly associated with the development of skin cancer in the future. The only way to prevent the development of skin cancer is to protect against ultraviolet radiation, which can be achieved through strategic awareness during childhood and adolescence. Objective. The aim of this work was to evaluate the impact of educational activities for rural and urban students to promote the use of sunscreens and prevent skin cancer. Materials and Methods: This study was carried out with students (9-12 years) of rural (n=70) and urban (n=70) schools in Rio Grande do Sul state, Brazil. The educational interventions were lectures and games. The impact of this strategy was evaluated through the application of a questionnaire before and after the interventions. Results: Before the intervention, it was found around 50% of rural and urban students were not aware of the damage caused by sun exposure, often exposing themselves to UV radiation without use sunscreen ( ~ 25 %) and at the most critical times of the day/year. After the lectures we observed an improvement in the behavior of the students with regard to sun exposure and knowledge about skin cancer. Conclusions: The results of this study emphasize the importance of prevention strategies for skin cancer and promoting the use of sunscreens based educational strategies. The interventions were of great value in relation to disseminating knowledge on the subject.