• Title, Summary, Keyword: uv-spectra

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Action Spectra of Apoptosis Induction and Reproductive Cell Death in L5178Y cells in UV-B Region

  • Mizuho Aoki;Yoshiya Furusawa;Higashi, Sho-ichi;Masakatsu Watanabe
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.454-456
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    • 2002
  • It is important to determine the action spectrum of UV-B radiation contained in the sunlight to estimate the risk of skin cancer. We have investigated action spectra for induction of apoptosis and reproductive cell death in L5178Y cells using the Okazaki Large Spectrograph at NIBB. L5178Y cells were exposed to light at different wavelengths in UV-B or UV-A region. Frequencies of apoptosis induction and reproductive cell death were determined by counting cells with chromatin condensation, and by the colony formation assay, respectively. The measured sensitivity spectra for the two end-points were in very good agreement. Sensitivity decreased steeply with increase of wavelength in UV-B region and remains nearly constant in UV-A region. The action spectra were also slightly steeper than that for the minimum erythematic dose (MED), but very similar to the light absorption spectrum of DNA in UV-B region. On the other hand, the spectra for both endpoints were similar to MED spectrum but not DNA spectrum in the UV-A region. Also different time-course and morphological difference of apoptosis were found between UV-B (long time, fragmentation) and UV-A (short time, shrinkage) region. These results suggest that DNA damage induced by UV-B light triggers apoptosis and reproductive cell death, but other damaged targets (membrane, protein and so on) trigger these effects in UV-A region.

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A Study on the Optical Properties by Material of Soft Contact Lens (소프트콘택트렌즈의 재료에 따른 광학적 특성에 관한 연구)

  • Son, Byeong-Ho;Jeong, Ju-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.2
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    • pp.27-30
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    • 2009
  • Purpose: Transmittance at UV-visible spectra range was measured to confirm the effect of wet/dry state of commercially available SCL on human eyes. Method: Commercially available five SCLs fabricated by different materials were selected to measure optical properties according to humidity. Results: A relatively high transmittance above about 80% in the visible spectra range of the SCLs were observed. In the UV spectra range, the wet samples showed higher transmittance than those dried except an unusual case. Conclusions: All the samples having a high optical properties in the visible spectra range exhibit a high transmittance in the UV region. Further research will be needed to develop new materials having a sharp absorption edge in the UV spectra range.

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Effects of UV Absorber and HALS(Hindered Amine Light Stabilizer) Addition in Water-soluble Acrylic Resin on Discoloration of Larix leptolepis (S. et Z.) Gordon (수용성(水溶性) 아크릴 수지(樹脂)의 자외선(紫外線) 흡수제(吸收劑)와 HALS 첨가(添加)가 일본잎갈나무의 변색(變色)에 미치는 영향(影響))

  • Kang, Kyoung-Taek;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.24 no.4
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    • pp.47-55
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    • 1996
  • UV transmission spectra of water-soluble acrylic resin films containing hydroxybenzophenolic, hydroxyphenylbenzotriazolic UV absorber and HALS(hindered amine light stabilizer) were investigated by exposure time(before exposure weathered for 160 and 320hours) in QUV Weather-Ometer. Also the YID(yellowness index difference), LID(lightness index difference) and CD(color difference) of dried water-soluble acrylic resin films and the coated woods of Larix leptolepis were analyzed by addition level of UV absorber(0, 1, 2 and 3%) and HALS(0, 0.5, 1 and 1.5%) and by exposure time in QUV Weather-Ometer. They showed no significant effects on UV transmission spectra of dried water-soluble acrylic resin films in the range of 300 to 400nm irrespective of exposure time. However, UV transmission decreased as increase of exposure time. UV transmission spectra were lower in dried water-soluble acrylic resin films containing hydroxybenzophenolic UV absorber and HALS than in these containing hydroxyphenylbenzotriazolic UV absorber and HALS in the range of 350 to 400nm. The least YID, LID and CD in the coated woods of Larix leptolepis appeared at the addition level of 3%, based on non-volatile content, in hydroxybenzophenolic and hydroxyphenylbenzotriazolic UV absorber, and of 1.5% in HALS to water-soluble acrylic resin.

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Photoisomerization of Cellulose Derivatives Obtained from Homogeneous System (균질계에서 얻은 셀룰로오스 유도체의 광이성질화 현상 연구)

  • No, Young-Ran;Park, Keun-Ho;Lee, Soo
    • Journal of the Korean Applied Science and Technology
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    • v.17 no.4
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    • pp.273-278
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    • 2000
  • Cellulose tosylate(CT) was prepared by reaction of cellulose with p- toluenesulfonylchloride in DMAc/LiCl homogeneous system. In order to study a reversible photoisomerization of disperse red 1(DR-1) attached on natural polymer, cellulose tosylate containing DR-1(DR-1/CT adduct) was prepared at $110^{\circ}C$ in DMAc, and the changes of UV/Vis spectra of its solutions and thick film were investigated by alternate irradiation technique. Form the UV/Vis spectra of DR-1/CT adduct dissolved in cosolvents, such as DMAc, DMAc/THF, DMAc/benzene, and DMAc/chloroform and irradiated with 360 nm and 450 nm ligths, we found out changes of UV/Vis spectra were reversible in all solvents systems and we found out changes of UV/Vis spectra were reversible at thick film, also.

Changes in Growth and Antioxidant Contents of Romaine Lettuce by Different UV Spectra

  • Jeong, Sung Woo
    • Journal of People, Plants, and Environment
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    • v.21 no.5
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    • pp.343-350
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    • 2018
  • The current study was conducted to determine the influence of irradiations of different UV spectra on plant growth and antioxidant compounds of two romaine lettuce cultivars('Caesar green' and 'Caesar red'). The UV treatments were consisted of three UV spectra; UV-A (314-400nm), FUV-B (290-400nm) and UV-B (274-400nm), using fluorescent lamps and irradiated for 2 hours at nighttime for 11 days under greenhouse. As the results, there were no differences in growth parameters and antioxidant compounds between UV-A treatments and control in two cultivars. On the other hand, FUV-B treatment increased significantly the contents of UV absorbing compounds, ${\beta}$-carotene, lutein, total phenolic compounds and anthocyanin in caesar green cultivar. It also increased UV absorbing compounds, total phenolic compounds and anthocyanin contents in caesar red cultivar without any growth reduction. UV-B treatment, however, decreased lutein, chlorophyll contents and caused growth reduction and physiological damage such as leaf chlorosis and wrinkle in both cultivars. Overall, the results indicate that supplemental FUV-B treatment, at least in part, may increase antioxidant compounds without any inhibitory effect on shoot growth in romaine lettuce. The results of the current study present a useful practical technique for increasing antioxidant compounds of romaine lettuce production in greenhouse horticulture.

Symmetry and Spectra of Complexes of Azo-Substituted Copper Phthalocyanine (Copper Phthalocyanine과 그 Azo 置換錯鹽들의 對稱과 Spectra)

  • Cho Nam-Sook;Kim Ki-Hwan;Hahn Chi-Sun
    • Journal of the Korean Chemical Society
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    • v.16 no.6
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    • pp.378-384
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    • 1972
  • The UV absorption spectra of the copper phthalocyanine and its azo derivatives in pyridine have been examined on the basis of symmetry operation, ligand field theory and molecular orbital consideration. The above treatment was also employed to determine the structure of the synthesized complexes.

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A Study on the UV-cut Properties of Cotton Fabrics Treated with UV-absorber (자외선 흡수제 처리 면직물의 소비성능 개선(제1보) - 자외선 차단성능에 관한 연구 -)

  • 강미정;권영아
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.5
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    • pp.925-932
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    • 2001
  • The influence of ultraviolet(UV)-ray in sun light on human skin has been noted. Textiles can provide protection against harmful UV-radiation. Normally UV-absorbing finishes are used to get better protection. The purpose of this study is to evaluate the UV-cut properties of cotton fabrics treated with UV-absorber. 2,2-dihydroxy-4,4-dimethoxbenzophenone, as UV-absorber was applied to 100% cotton fabric. Reagents added in finishing solution were Triton X-100, polyethylene glycol 400, and $MgCl_2{\cdot}6H_2O$, and C.I. Direct Red 81. Both untreated and treated cotton fabrics were exposed to a xenon arc lamp for 20 and 80 hours. UV absorption spectra of finishing solutions and UV transmission spectra of fabrics were measured by the UV/VIS spectrophotometer. The results of this study can be summarized as follows. The results of this study can be summarized as follows. Absorption and the related transmission spectra were modified in a controlled way with UV-absorber. Absorption effect of UV-absorber was improved by adding Triton X-100, PEG 400, and $MgCl_2{\cdot}6H_2O$ in finishing solution. The UV absorption of finishing solution was in the following order: U/D/T/P/M>D/T/P/M> D/T> D/P, D>U/T/P/M>U/T>T/P/M>T. The UV transmittance of cotton fabrics was remarkably decreased by the application of UV-absorber and additives. The UV-cut properties were most improved by the application of U/D/T/P/M.

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The Dyeing Properties of Korean Knotweed Extract( II ) - The UV-visible Spectrophotometric Characteristics of Korean Knotweed Extracts - (호장근 추출액에 의한 염색성(II) -호장근 추출액의 자외 . 가시부 분광 특성 -)

  • 김미숙;최석철
    • Textile Coloration and Finishing
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    • v.13 no.5
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    • pp.298-305
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    • 2001
  • The Purpose of this study was to investigate spectrophotometric characteristics of Korean knotweed extracts. The properties were evaluated by it's extracting solvent, effect of metallic ion, variations of pH values and effect of light exposure. The results were as following; The highest absorbance was found in methanol extract of Korean knotweed, while the lowest absorbance was carbon tetrachloride extract. The UV-vis. spectra of Korean knotweed colors in several solvents showed hypsochromic shift of $n->\pi^*$ transition with the polarity of solvent. Absorbance and peak of UV-vis. spectra of Korean knotweed colors became lower and broader by addition of metallic ion. The light stability in irradiation with xenon ]amp of the color solution with Cu were higher than those of Al and Fe. The UV-vis. spectra of Korean knotweed extracts in various pH values showed bathochromic shift under alkaline condition, and their Peaks disappeared after 5 hours exposure.

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Mg II LINE VARIATION OF 32 CYGNI

  • Kang, Young-Woon
    • Journal of Astronomy and Space Sciences
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    • v.9 no.2
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    • pp.154-164
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    • 1992
  • The Mg II lines been extracted from the IUE archival spectra of 32 Cygni to investigate the effect of the atmospheric eclipse. The UV light curve has been reduced from the continuum flux at the center wavelength of 2807.5 ${\AA}$ in the IUE spectra. The equivalent width of the Mg II k absoption line has been measured for each spectra. The results of the light variation and flux tracing of the absorption line at the vicinity of the primary eclipse confirmed the atmospheric eclipse. The atmospheric effect lasted until the phase 0.06 in the absorptin line tracing, while it lasted until the phase 0.02 in the UV light curve, respectively.

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Phototoxicity of Melatonin

  • Kim, Young-Ok;Chung, Hye-Joo;Chung, Seung-Tae;Kim, Jin-ho;Park, Jae-Hyun;Kil, Kwang-Sup;Cho, Dae-Hyun
    • Archives of Pharmacal Research
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    • v.22 no.2
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    • pp.143-150
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    • 1999
  • melatonin (MLT), N-acetyl-5-methoxytryptamine, is mainly secreted by the pineal gland. The ultraviolet (UV), infrared (IR) and 1H-NMR spectra of irradiated and non-irradiated MLT were measured, and phototoxicity tests of MLT, anthracence (positive control) and sodium lauryl sulfate (SLS, negative control) were performed. The methods employed include both in vitro test such as MTS assay using the human fibroblast cell and yeast growth inhibition assay using Candida albicans and in vivo method using the skin of guinea pig. UV absorption spectra and 1H-NMR spectra of MLT were changed by UVA (365 nm, 15 J/$\textrm{cm}^2$), but IR spectra of MLT were not changed. The fifty percent inhibitory concentration (IC50) ratio (UV-/UV+) of MLT was 10. The inhibition zone of irradiated-paper disks treated with MLT was not observed. According to the results of histophathological examination, no pathologic lesion was observed in the non-irradiated group, but slight degeneration of keratinocytes in the epidermis, homorrhage and vasodilation in dermis were observed in the irradiated group. These results indicated that the molecular structure of MLT is altered by UVA to unidentified photoproducts and a moderate phototoxicity of MLT is predicted.

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