• 제목/요약/키워드: 자외선 조사

검색결과 948건 처리시간 0.029초

Characterization of UV-Inducible Gene (UVI-180) in Schizosaccharomyces pombe (분열형 효모 Schizosaccharomyces pombe에서 자외선 유도유전자 UVI-180의 특성 연구)

  • Park, In-Soon
    • Environmental Analysis Health and Toxicology
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    • 제18권3호
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    • pp.225-230
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    • 2003
  • 본 연구는 DNA 상해유도기작을 규명하기 위하여 하등 진핵생물인 분열형 효모 Schizosaccharomyces Pombe로부터 subtraction hybridization방법을 이용하여 자외선 유도 유전자인 UVI-180을 분리하고 그 유전자 구조와 발현양상을 조사하였다. UVI-180유전자의 발현양상을 Northern hybridization 방법으로 살펴본 결과 자외선(ultraviolet-light)조사 1시간 후에 최대의 발현 증가를 나타내었다. 반면 알킬화제인 MMS(methyl methanesulfonate)처리에 의해서는 전혀 발현이 증가되지 않았다. 이 결과 UVI-180유전자는 DNA상해에 따라 각기 다른 발현양상을 나타냄을 알 수 있었다. 유전자의 기능을 알기 위하여 null-mutant세포 주를 제조하여 그 특성을 살펴본 결과 이 유전자는 세포의 성장에 필수적인 유전자임을 알 수 있었다.

분화와 발생양상의 조절기작에 관한 연구: 자외선 조사와 수정난의 회전이 배, 복축 극성의 결정에 미치는 영향

  • 정해문
    • The Korean Journal of Zoology
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    • 제25권3호
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    • pp.107-114
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    • 1982
  • A combination of ultraviolet irradiation and egg rotation was applied to Korean frogs to study the mechanisms of the establishment of the dorsal-ventral polarity. Rotation of the uncleaved egg was capable of preventing the characteristic syndromes associated with UV irradiation. As well, brief rotation of the egg before cleavage relocates the site of dorsal lip to a novel location in the embryo at gastrula stage. That is, the dorsal lip appeared on the opposite side to gravity at the rotation of the egg. Above results were discussed with the informations obtained from other anuran and urodele species, and were interpreted in terms of regulating mechanisms for early embryogenesis.

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Photodegradation and Degradation Product of Piperophos (Piperophos의 광분해 및 분해생성물에 대한 연구)

  • 민경진
    • Journal of Food Hygiene and Safety
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    • 제19권2호
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    • pp.97-103
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    • 2004
  • The present study was performed to investigate photodegradation rate constants and degradation products of piperophos by the USEPA method. The pesticide was very stable in 16 days exposure of sunlight from October 3 to 22, 2003 and humic acid had no sensitizing effect on the photolysis of each pesticide in sunlight. In the UV irradiation test, piperophos was rapidly degraded as increasing UV intensity. In case of UV irradiation with TiO$_2$ and with TiO$_2$ powder amount, degradation of piperophos was slower than UV irradiation. In order to identify photolysis product, the extracts of degradation product was analyzed by GC/MS. The mass spectrum of photolysis product of piperophos was at m/z 166. It was suggested that the photolysis products of piperophos was O, O-dipropyl phosphorodithioate.

A study on the polarized spectacle lens with photochromic UV blocking function of refractive index 1.60 (굴절률 1.60 광변색성 자외선 차단기능을 갖는 편광안경렌즈 연구)

  • Han, Doo-Hee
    • Journal of Convergence for Information Technology
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    • 제8권1호
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    • pp.147-152
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    • 2018
  • A polarizing spectacle lens having a perfect blocking of ultraviolet light and a partial blocking of blue light and having photochromic properties has been developed. It is a functional spectacle lens which can be used as a spectacle lens in the daytime, which plays a role of sunglass in a space with strong ultraviolet rays, dramatically reducing glare caused by late-night driving or reflected light. Photochromism was recovered in 0.5 second dark reaction and 3 seconds recovery time. The polarization function was about 95%. Ultraviolet rays were completely blocked and blue light was reduced by about 30%. A lens that combines photochromic and UV blocking and polarization functions is the first attempt at investigating the domestic market.

Sensory Evaluation of Sunscreen and Application for Product Development (자외선차단 화장품의 관능적 특성평가와 제품개발에 대한 응용)

  • 정수정;심소연;선보경;문성준
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 한국감성과학회 2001년도 추계학술대회 논문집
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    • pp.245-250
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    • 2001
  • 화장품 사용 시 소비자가 가장 중요하게 느끼는 요인은 효과와 촉감이라고 볼 수 있다. 특히 반복적인 사용을 위해서 쾌적한 촉감은 필수 조건이다. 그런데, 촉감은 사용하는 사람 자신의 감각에 의존하는 것이므로, 이러한 화장품의 촉감을 포함하는 성능을 평가하기 위해서 사람에 의한 최종평가는 필수적인 단계이다. 따라서, 여러 특성의 강도를 측정하는 분석형 관능평가와 소비자의 선호도를 조사하는 기호형 관능평가의 필요성이 요구되며, 두 결과를 종합적으로 고려하는 것이 바람직할 것이다. 우리는 훈련된 전문패널에 의해 다양한 자외선차단 크림과 로션들에 대한 분석형 관능평가를 실시하였다. 그 결과, 자외선차단 제품의 관능속성 평가의 주요인은 잔여감 요인과 발림성 요인으로 나타났으며, 이 결과에 따라 제품들을 2차원 공간 상에 위치하였다. 이 중 몇 제품을 선택하여 20대 후반 여성소비자를 대상으로 기호형 관능평가를 실시하였다. 평상시 실제 화장단계에서 인지되는 자외선차단제품에 대한 용어들은 촉촉함 및 도포균일성 요인/흡수속도 요인의 두가지 요인으로 분류되었다. 이상적인 자외선차단제품의 사용감은 너무 촉촉하지도 매트하지도 않으면서, 흡수속도는 빠르고 화장밀림이나 번들거림이 적은 사용감을 나타내는 특성쪽으로 나타났다.

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Quality Preservation of Shredded Carrots Stored in UV LED Packaging System (자외선 LED 포장용기 시스템에 의한 포장절단당근의 품질보존)

  • Kim, Nam Yong;Lee, Dong Sun;An, Duck Soon
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제43권1호
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    • pp.135-140
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    • 2014
  • Pre-storage ultra-violet (UV) light treatment on fresh produce is known to inactivate the contaminated microorganisms, activate the defense system, and delay ripening extending the shelf life. As UV light emitting diode (LED) becomes available at a relatively low price, continuous or intermittent UV treatment during chilled storage is possible in a container or package. This study attempted an in situ UV LED treatment on fresh produce stored under a refrigerated container in order to see its potential in the fresh produce storage and further optimize its application conditions. The effect of in-container UV LED irradiation on the quality preservation of shredded carrots was investigated in the air and modified atmosphere (MA) conditions. Two sets of experiment with Escherichia coli inoculation and with natural microbial flora in the air (two 30 minute on-off cycles of 1 $diode/dm^2$ per day at a location above 2 cm) showed a clear and significant effect of the UV LED irradiation on the suppression of microbial growth: 280 nm was the most effective by maintaining a lower microbial count by at least 0.5 log (CFU/g) throughout the 6 day storage period. The carotenoids content of shredded carrots subjected to UV LED treatment at 365 and 405 nm in the air was higher than that of the control shredded carrots. In MA condition of $O_2$ of 1.2~4.3% and $CO_2$ of 8.4~10.6% being indifferent with LED wavelengths, 280 nm UV LED irradiation was also effective in inhibiting the microbial growth. While there was no observed difference in the carotenoids content between untreated and UV LED-treated shredded carrots in MA, UV LED irradiation at 365 and 405 nm was slightly better in DPPH radical scavenging activity. The use of UV LED in storage container or package seems to give the benefits of preserving the microbial and nutritional qualities of minimally processed fruits and vegetables.

A Test to Compare the Water Resistance Sun Protection Factor of General Water, Artificial Seawater, and Natural Seawater of Sunscreen (자외선 차단제의 일반 물, 인공 해수, 자연 해수의 내수성 차단지수를 비교하기 위한 시험)

  • Hyoung Hoon Hwang;Eun Young Kang;Su Yeong Kim;Hui Jeong Jung;Jun Seong Yang;Won Kyu Hong;Hong Suk Kim
    • Journal of the Society of Cosmetic Scientists of Korea
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    • 제49권4호
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    • pp.349-354
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    • 2023
  • Sunscreen is a product that protects against ultraviolet rays by blocking and scattering ultraviolet rays, and has now become a daily necessity beyond cosmetics. Applying sunscreen is a common and easy way to prevent skin damage caused by ultraviolet rays. Due to its significance, the evaluation of sunscreen has evolved since its regulation by the FDA in 1978, progressing to standardized methods established by ISO. Additionally, to assess the loss of sunscreen due to activities such as water exposure or sweating, the Ministry of Food and Drug Safety in Korea and ISO have established protocols for evaluating the water-resistant sun protection factor (SPF). However, existing evaluations of water resistance have been mainly confined to test methods involving plain water, and methods accounting for the impact of seawater during activities like beach leisure, sports, and recreation are yet to be established. Based on the existing guidelines for testing the water-resistant UV protection index, this study compared the water-resistant UV protection index in water, artificial seawater (salt water) and natural seawater (sea water) to evaluate the UV protection index in real-world situations such as marine leisure, sports, and leisure activities. Through these results, we were able to compare the differences between water resistance sun protection index tests in ordinary water, artificial seawater, and natural seawater, and suggest a method for water resistance sun protection index tests using natural seawater.

Temperature dependence of photoluminescence for blue and green light emitting porous Ge and spark processed Ge (청색 및 녹색 발광 다공성 Ge 및 스파크 제조된 Ge의 광발광의 온도의존성)

  • 장성식
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • 제8권3호
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    • pp.442-447
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    • 1998
  • Visible photoluminescence (PL) has been observed generally in the blue and green spectral region from anodically etched porous Ge as well as spark processed Ge. Porous Ge which is prepared by anodic etching without UV light illumination displays the PL peak max of 52 nm (2.38 eV), while porous Ge with UV light illumination exhibits PL peak blue shift to a 470 nm (2.63 eV). Spark processed Ge shows a PL peak max of 520 nm with shoulder peaks at 420 nm and 610nm. The values of energy shift as a function of decreasing temperature between 300 K and 20 K is 0.53 and $1.89\;meVK^{-1}$ for anodic etched Ge without UV illumination and with UV illumination, respectively. On the contrary, no continuous blue shift of PL peak as a function of decreasing temperature is observed for the green luminescing spark processed Ge. From the results of PL as a function of temperature the origin of blue and green luminescing anodically etched Ge as well as spark processed Ge is discussed.

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Synthesis of Macroporous TiO2 Microparticles for Anti-Bactericidal Application (거대 기공을 갖는 다공질 TiO2 분말의 살균 효과)

  • Roh, Seong Hoon;Kim, Jeong Keun;Cho, Young-Sang
    • Korean Chemical Engineering Research
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    • 제56권4호
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    • pp.524-535
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    • 2018
  • In this study, macroporous titania powders were synthesized utilizing the emulsion-assisted self-assembly to apply the removal of B. subtilis under UV irradiation, and the results were compared with the bactericidal effect of commercial titania nanoparticles. By changing the pore size of the porous titania powder, the reduction of B. subtilis by photocatalytic effect was measured, and the bactericidal capacity of the porous particles according to the pore size was compared in order to derive the optimum condition of the sterilization experiment. It was observed that the sterilization effect increased as the pore size became smaller, and it was confirmed that more than 50% of B. subtilis cold be removed for 1 hour of UV irradiation. Also, in order to promote the generation of active chemical species, a diluted solution of hydrogen peroxide was combined with the photocatalytic sterilization method, resulting in the removal of most of the strain after ultraviolet irradiation for 1 hour.

Mutation and Selection of Agrobacterium tumefaciens Arginine Auxotroph by UV Irradiation (자외선 조사(照射)에 의한 Agrobacterium tumefaciens Arginine 요구주(要求株)의 유도와 선발)

  • Lee, Yearn;Park, Ro-Dong;Kim, Kwang-Sik
    • Applied Biological Chemistry
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    • 제28권2호
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    • pp.92-97
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    • 1985
  • UV irradiation method was applied to Agrobacterium tumefaciens A 136 to obtain arginine auxotrophic mutant which is applicable as a host of Ti-plasmid. When the bacterial growth was measured at 600 nm, it showed the exponential phase between 7 and 16 hours after 2% inoculation (v/v) in TY medium and the generation time of 4.8 hours. Survival rate of $1{\sim}0.1%$ was reserved when irradiated at the intensity of $800\;{\mu}w/cm^2$ for $30{\sim}50sec$. Fifteen mutants were selected among 5,000 colonies after UV irradiation. Two of them were identified as arginine auxotrophs, three of them as asparagine auxotrophs, ana the other not as arginine, asparagine, glycine nor cysteine auxotrophs.

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