• 제목/요약/키워드: Ultraviolet-B (UV-B)

검색결과 248건 처리시간 0.032초

Effects of Ultraviolet-B Radiation on Growth and Photosynthesis in Sunflower Seedlings

  • Kim, Tae-Yun;Hong, Jung-Hee
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2006년도 추계 학술발표회 발표논문집
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    • pp.455-457
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    • 2006
  • The effects of UV-B irradiation on the growth and photosynthetic activity were investigated in seedlings of sunflower(Helianthus annuus L.). The first leaves irradiated with UV-B were retarded in growth but simultaneously acquired a remarkably decreased chlorophyll fluorescence ratio compared with the non-irradiated leaves. The Fv/Fm ratio decreased by 13 % compared to the control after 2 d, and was kept to be lower than the control level until 5 d. From the results it is suggested that UV-B radiation may induce reduced biomass production and decrease in photosynthetic rate in sunflower plants.

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자외선 B 조사 마우스에서 표피멜라닌세포 변화에 대한 헤모힘의 방어효과 (Protective Effect of HemoHIM on Epidermal Melanocytes in Ultraviolet-B irradiated Mice)

  • 이해준;김종춘;문창종;정우희;박혜란;조성기;장종식;김태환;김성호
    • Journal of Radiation Protection and Research
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    • 제36권2호
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    • pp.93-98
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    • 2011
  • C57BL/6 마우스에서 자외선 B(UV-B) 조사에 의한 표피 멜라닌세포의 변화에 대한 헤모힘의 효과를 관찰하였다. 마우스에 UV-B를 매일 $80\;mJ{\cdot}cm^{-2}$ ($0.5\;mW{\cdot}sec^{-1}$)씩 7일간 조사하고 헤모힘을 UV 조사 전 또는 조사 후에 복강내주사, 경구투여 또는 피부에 도포하여 멜라닌세포 형성 억제효과 및 형성된 멜라닌세포에 대한 미백효과를 dihydroxyphenylalanine (DOPA) 염색으로 관찰하였다. 마우스의 귀등쪽 표피를 분리하여 관찰한바, 정상대조군에서는 $mm^2$당 13~15개의 멜라닌세포가 관찰되었다. 멜라닌세포 형성 억제 실험에서는 평균치를 기준으로 복강내주사군에서 44.9%, 경구투여군에서는 35.6%의 억제효과를 보였고, 피부도포군에서는 30% 이상의 유의성 있는 억제 효과가 관찰되었다. 형성된 멜라닌세포의 감소 효과 실험에서는 평균치를 기준으로 복강내주사군의 경우 3주 및 6주에 각각 18.3%, 12.5%의 감소 효과가 관찰되었고, 경구투여군에서는 3주 및 6주에 각각 16.9%, 20.4%의 감소 효과가 관찰되었으며, 피부도포군의 경우 3주에 32.0%, 6주에 31.2%의 감소 효과를 보였다. 이상의 결과는 헤모힘이 UV에 의한 멜라닌세포 형성 억제제 및 미백제로서의 적용 가능성을 제시하였다. 구성 단미생약, 유효성분, 멜라닌세포 형성 억제 및 형성된 세포의 감소 촉진에 관여하는 작용 기전에 대한 추가 연구가 필요하다.

A Comprehensive Study for Two Damage Sites of Human Hair upon UV-B Damage

  • Song, Sang-Hun;Son, Seongkil;Kang, Nae Gyu
    • Korea Journal of Cosmetic Science
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    • 제2권1호
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    • pp.1-10
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    • 2020
  • Protection mechanisms for skin damage of ultraviolet (UV) absorbers in personal care products for protection against UV are well studied, but not for hair protection. The purpose of this study is to describe and compare the changes of physical property produced in human hair by doses of the UV-B exposure causing protein degradation. To observe the change of physical properties in hair, the experimental intensity of UV-B exposure has been established on the basis of statistical data from official meterological administration as daily one hour sunlight exposure for two weeks. Polysilicone-15, ethylhexyl methoxycinnamate (OMC), and octocrylene were employed for UV-B absorber, and those were treated to hair swatch by rubbing wash through shampoo and conditioner. Bending rigidity displayed kinetically successive reduction at high doses of UV exposure up to the 8,000 s, and exhibited different level at each sample of UV-B absorber. However, the values of Bossa Nova Technologies (BNT) for shinning factor were already saturable at the 2,000 s exposure except that treated with polysilicone-15. The differential scanning calorimetry (DSC) to measure a strength of inner protein produces a successive reduction of enthalpy as like a reduction of bending rigidity upon UV exposure. Surface roughness from lateral force microscope (LFM) acquired immediately after UV exposure show a saturable frictional voltage which has been also found in a saturable BNT data as the time of UV exposure increases. Through researching the DSC and the LFM, shinning of hair was much correlated to the protein damage at the surface, and bending rigidity could be regulated by the protein structural damage inside hair. Therefore, the optimization of efficient strategy for simultaneous prevention of hair protein on the surface and internal hair was required to maintain physical properties against UV.

양산형 일광차단모의 개발(제1보) -고안 및 마네킹 착용실험- (Development of the sunshade hat with a large brim(Part I) -Development and test with manikins-)

  • 김경수;최정화
    • 한국의류학회지
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    • 제26권8호
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    • pp.1177-1185
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    • 2002
  • This study was to develop the sunshade hat which reduced stress from solar radiation and ultraviolet radiation (UV), in order to keep the farmer's health and to promote their work efficiency. The new sunshade hat with a large brim, special structure for ventilation, stability and portability was designed and tested with manikin heads outdoors. Two newly designed sunshade hats(A, B) and three existing hat were tested Sunshade hat A made of double fabric with aluminum coating-nylon and black cotton cloth with a polyester mix(T/C) was the most protective from solar radiation. Sunshade hat B with larger brim was the most protective from ultraviolet radiation, even though it was made of aluminum coating-nylon single fabric.

홍화 염색 모직물의 자외선에 의한 성능 변화 연구 (A Study on the Properties Changes of Wool Fabrics Dyed with Safflower under Ultraviolet(UV)-Light)

  • 신윤숙;최승연
    • 한국의류산업학회지
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    • 제10권2호
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    • pp.249-253
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    • 2008
  • The purpose of this study was to investigate the properties changes of wool fabrics dyed with safflower red and yellow colorants under Ultraviolet(UV)-light. For this purpose, the wool fabrics dyed with safflower red and yellow colorants were compared with each other after uv-light exposure in terms of K/S value, color changes(${\Delta}E$), morphology, and strength retention. K/S value rapidly decreased with increasing exposure time, but K/S value of the samples dyed with safflower yellow colorants decreased less than that of the samples dyed with safflower red colorants. In color changes, as increasing exposure time, $L^*$ and $b^*$ increased, $a^*$ decreased, and thereby ${\Delta}E$ increased in the samples dyed with safflower red colorants, $L^*$ increased, $a^*$ and $b^*$ decreased, and so ${\Delta}E$ increased in the samples dyed with safflower yellow colorants, indicating fading away by uv-light and changes of hue, value and chroma value. But the color change of samples dyed with safflower yellow colorants was less than that of samples dyed with safflower red colorants. SEM pictures showed a severe degradation by uv exposure, regardless of colorants type. Tensile strength slowly decreased until 14 days, and rapidly decreased until 21 days and slowly decreased. Strength retention of the samples dyed with safflower yellow colorants was higher than that of the samples dyed with safflower red colorants.

Parameterization Model for Damaging Ultraviolet-B Irradiance

  • Kim, Yoo-Keun;Lee, Hwa-Woon;Moon, Yun-Seob
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • 제3권1호
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    • pp.41-56
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    • 1999
  • Since UV-B radiation measuring networks have not been established, numerical models which calculate the flux from other readily available meteorological measurements may play an important role. That is, such a problem can be solved by using parameterization models such as two stream approximation, the delta-Eddington method, doubling method, and discrete ordinate method. However, most UV-B radiative transfer models have not been validated with measurements, because such models are not intended as practical computational schemes for providing surface estimates of UV-B radiation. The main concern so far has been to demonstrate model sensitivity for cloudless skies. In particular, few have been concerned with real cloud information. Clouds and aerosols have generally been incorporated as constituents of particular atmospheric layers with specified optical depths and scattering properties. The parameterization model presented here is a combination of a detailed radiative transfer algorithm for a coludless sky radiative process and a more approximate scheme to handle cloud effects. The model input data requires a daily measurement of the total ozone amount plus a daily record of the amount and type of cloud in the atmosphere. Measurements for an examination of the models at the Department of Atmospheric Sciences, Pusan National University have been takenfrom February, 1995. These models can be used to calculate present and future fluxes where measurements have not been taken, and construct climatologies for the period before ozone depletion began.

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Effects of solar UV radiation on photosynthetic performance of the diatom Skeletonema costatum grown under nitrate limited condition

  • Li, Gang;Gao, Kunshan
    • ALGAE
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    • 제29권1호
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    • pp.27-34
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    • 2014
  • Availability of nutrients is known to influence marine primary production; and it is of general interest to see how nutrient limitation mediates phytoplankton responses to solar ultraviolet radiation (UVR, 280-400 nm). The red tide diatom Skeletonema costatum was cultured under nitrate (N)-limited and N-replete conditions and exposed to different solar irradiation treatments with or without UV-A (315-400 nm) and UV-B (280-315 nm) radiation. Its photochemical quantum yield decreased by 13.6% in N-limited cells as compared to that in N-replete ones under photosynthetically active radiation (PAR)-alone treatment, and the presence of UV-A or UV-B decreased the yield further by 2.8 and 3.1%, respectively. The non-photochemical quenching (NPQ), when the cells were exposed to stressful light condition, was higher in N-limited than in N-replete grown cells by 180% under PAR alone, by 204% under PAR + UV-A and by 76% under PAR + UV-A + UV-B treatments. Our results indicate that the N limitation exacerbates the UVR effects on the S. costatum photosynthetic performance and stimulate its NPQ.

Preventive Effect of Natural Pigments Against Ultraviolet B-induced Cell Death in HaCat Cells

  • Lim, Jae-Chung;Bae, Chun-Sik;Jeong, Soo-Young;Boo, Hee-Ock;Hwang, Seong-Jin;Lim, Seul-Ki;Park, Min-Jung;Kim, Jong-Chun;Kang, Seong-Soo;Han, Ho-Jae;Park, Soo-Hyun
    • 대한의생명과학회지
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    • 제17권1호
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    • pp.55-60
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    • 2011
  • Skin is a physical barrier against diverse injury and damages. Exposure to ultraviolet (UV) radiation causes detrimental skin injuries such as inflammation and cell death. The value of natural pigments could be applied to many usages including cosmetics. This study was conducted to examine the protective effect of natural pigments extracted from mulberry, balsam pear, purple-colored sweet potato, pehmannia root, gardenia fruit, and black rice against UV-induced cell death in HaCaT cells, human keratinocyte cell lines. In the present study, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr induced cell death in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In addition, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr also increased lipid peroxide (LPO) formation, compared to control in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In conclusion, the extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice prevented the UV-B-induced cell apoptosis via the inhibition of oxidative stress in HaCaT cells.

자외선 B를 조사한 마우스 표피멜라닌세포 변화에 대한 분죽(Phyllosrachys nigra var. henenis Strapf)잎 추출물의 효과 (The Effect of Bamboo (Phyllostachys nigra var. henenis Strapf) Leaf Extract on Epidermal Melanocytes in Ultraviolet B-irradiated Mice)

  • 이해준;채세림;김성호
    • Journal of Radiation Protection and Research
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    • 제32권2호
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    • pp.59-64
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    • 2007
  • C57BL/6 마우스에서 자외선 B(UVB)조사에 의한 표피 멜라닌세포의 변화에 대한 대나무(분죽, Phyllostachys nigra var. henenis Suapf ) 잎 추출물 (BLE)의 효과를 관찰하였다. 마우스에 UVB를 매일 $80mJ/cm^2(0.5mW/sec)$씩 7일간 조사하고 BLE를 UV조사 전 또는 조사 후에 복강내주사 또는 피부에 도포하여 멜라닌세포 형성 억제효과 및 형성된 멜라닌세포에 대한 미백효과를 dihydroxyphenylalanine (DOPA) 염색으로 관찰하였다. 마우스의 귀등쪽 표피를 분리하여 관찰한바, 정상대조군에서는 $mm^2$당 11-16개의 멜라닌세포가 관찰되었으며, UV조사 일주일 후 발달된 가지를 가진 DOPA 양성 멜라닌세포는 급격히 증가하였다. 멜라닌세포 형성 억제 실험에서는 평균치를 기준으로 복강내 주사군에서 29.9%, 피부도포군에서 33.3%의 유의성 있는 억제 효과가 관찰되었으며, 형성된 멜라닌세포의 감소 효과 실험에서는 평균치를 기준으로 복강내 주사군의 경우 6주에 24.4%의 감소 효과가 관찰되었고, 피부도포군의 경우 3주에 21.0%, 6주에 10.4%의 유의성 있는 감소 효과를 보였다. 이상의 결과는 BLE가 UV에 의한 멜라닌세포 형성 억제제 및 미백제로서의 적용 가능성을 제시하였다.