• 대한화장품학회지
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• 제23권2호
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• pp.63-70
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• 1997

It has been observed that local increase in melanin synthesis or uneven distribution can cause local hyperpigmintation or spot. Pigmentary disorders are caused by various factors, including inflammation, imbalance of hormones, and genetic disorder. Recently the harmfulness of Ultraviolet radiation is increasing due to destruction of ozone layer. Excessive exposure to UV radiation caused post-inflammatory pigmentation. Most women want to avoid uneven skin pigmentation. To satisfy this desire many cosmetic companies have been developing melanogenesis inhibitors and finding promising active agents for use in cosmetic preparations for skin whitening. In cosmetic preparations, many inhibitors such as kojic acid, arbutin, ascorbic acid, and licorice extracts6 have been used as whitening purpose. Plant extracts having an inhibitory effect on melanin formation may be a good choice for cosmetic purpose because of their relatively lower side effects. Therefore, we screened 285 plant extracts for their inhibitory activity in tyrosinase. Of the plant extracts, ramulus mori extracts showed potent tyrosinase inhibition activity. We also identified the active compound in the extract.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.5-10
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• 2003

This paper explores not only emerging scientific problems but also the difficulties communicating air quality issues into an increasingly sensitive the public and policy arena. The public understanding and trust in air pollution information and indices may be very different to the notions of validity or accuracy that are important for a scientist. We operate in a world where openness requires us to reveal both the difficulties and disagreements in our understanding of the polluted atmosphere. Yet this can be confusing and increase complexity in situations where clear political and social decisions are required. I am going to examine these issues, starting with questions of what substances we regard as pollutants and the difficulties of getting the correct balance of concern given the broadening the base of chemicals emitted to the environment. There are also questions of exposure particularly in terms of vulnerable populations, who may spend large amounts of time indoors, where air is rarely monitored. In contemporary society there are pollution problems that extend far beyond urban areas and we have to consider regional issues such as windblown dusts, smoke from forest fires along with issues of the emission of green house gases and ozone depleting substances. Finally I will discuss the issues of communicating with a concerned public and sceptical politicians and the troubling interface between technological and sociological control. Such complexity is often missed in a maze of seemingly stronger political and social needs.

• 보존과학연구
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• 통권30호
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• pp.47-61
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• 2009

Cultural heritages are affected by various environmental factors. Main factors are temperature, humidity, light and indoor air pollutants such as ozone, nitrogen oxides. Especially humidity condition is very important. Low humidity condition can cause contraction and high humidity condition can lead to growth of microorganism. This study is conducted to appraise an applicability of the Humidity Indicator which is one of the simple method for humidity control. The Humidity Indicator shows the humidity conditions through color change. Therefore, photometer was used to correctly measure the color change of Humidity Indicator. As a result of lab test, Humidity Indicators was stabilized after one hour from en exposure in a certain humidity condition and the indicators indicated clear correlations between color changes of Humidity Indicators and humidity conditions. Some Humidity Indicators which had been selected through the lab tests were applied to preservation facilities of cultural heritages and the indicators indicated closed correlations with humidity conditions in indoor of facilities.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.157-163
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• 1995

The ultraviolet blocking agents used to skincare are largely classified ultraviolet scattering agent and ultraviolet absorbent agents. There are UVC, UVB, and UBA in ultraviolet ray(UV) showing shorter wavelength than visible light. Both visible light and UVA give rise to 1st dark-skinned phenomena. On exposure of the skin to UV, phenomena of skin variation are termed sunburn or suntan. There are chronic and acute adverse reactions in skin response to UV. The latter is caused by UVB, which has mainly effects on the skin. But lately due to destruction of ozone layer, UVA has more serious irritation on the skin than UVB. In this paper spectrometric properties of UV absorbent agents such as PABA, octyl-PABA, Urocanic acid, and 2-hydroxy-4-methoxy benzophenone in vitro have been investigate. As results, it was found that the three fomer were more suitable than the last. UV scattering measurements on the sample used inorganic pigments showed that pigments containing titanium dioxide had a better scattering effects than the inorganic pigments such as $Fe_2O_3$, $Al_2O_3$, etc.

• Journal of Ecology and Environment
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• 제29권1호
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• pp.41-47
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• 2006

We investigated the enect of $O_3$ on the photosynthetic characteristics of tree of heaven (Ailanthus altissima) that is naturalized plant and used as restoration plant for contaminated area. Two-year-old seedlings were planted to pots and transferred into closed $O_3$ chamber. Photosynthetic pigments contents and photosynthetic characteristics were measured every three weeks under 100 pub $O_3$ fumigation. There was no visible foliar injury by $O_3$ exposure and contents of photosynthetic pigments did not show significant differences between control and $O_3$-treated seedlings. Also there were no significant differences in stomatal conductance, and water use efficiency. But photosynthetic rate and apparent quantum yield (AQY) of $O_3$ treated seedlings were reduced after nine weeks of ozone fumigation. In addition, the reduction of carboxylation efficiency and photorespiration were observed in the leave of $O_3$ treated seedlings after six weeks. In accordance with our result, carbon fixation system of A. altissima was most sensitive to $O_3$ stress to evaluate physiological damage induced by $O_3$.

• 정보저장시스템학회논문집
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• 제9권2호
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• pp.42-47
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• 2013

In this study, we have experimentally analyzed how the surface properties of transparent electrode layer influence the photovoltaic performance of bulk heterojunction organic solar cell by the contact angle measurement and X-ray photoelectron spectroscopy(XPS) observation. As a result, the power conversion efficiency of test devices improved from 0.64% to 1.83% and 2.15% by UV-ozone exposure and $O_2$ plasma treatment, respectively. Thus, we conclude that the surface activation process is very important for better performance and stability in addition to the cleaning process of carbonate residue on the surface.

• 한국전자통신학회논문지
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• 제17권3호
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• pp.499-506
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• 2022

2021년 동해북부선 착공으로 비무장지대(Demilitarized Zone:DMZ)의 평화적 활용의 기대치가 높아지고있다. 이에 따라 비무장지대를 안보생태관광으로 활용한 인근 해변에서의 레저관광 활동에 대비해야 한다. 그러나 오존층의 파괴로 인한 지표면 자외선(Ultravilolet:UV) 양의 증가에도 불구하고 아직까지 자외선 노출 위험가이드라인이 없다. 본 논문에서는 원격탐사를 이용한 비무장지대 인접 해안에서의 자외선 반사량 측정하고 분석하였다. 제시된 결과가 인근지역 레저관광 활동에서의 자외선 가이드라인 마련에 기초자료로 활용되기를 기대한다.

• 한국환경농학회지
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• 제11권1호
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• pp.41-49
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• 1992

토마토의 오존에 대한 내성을 증대시키고자 생장 외화제인 uniconazole을 0, 0.001, 0.01, 0.1, 0.2mg/pot의 농도를 토양주입하고, 0.3ppm이 오존에 처리하였던 바 다음과 같은 결과를 얻었다. 1. Uniconazole은 0.001mg/po1의 낮은 농도에서도 식물체를 크게 왜화시켰으며, 왜화정도가 클수록 오존에 대한 내성을 증대시켜 무처리구의 25% 피해에 비하여 0.01mg/pot의 낮은 농도처리에서도 10% 이하로 피해를 경감시켰다. 2. Uniconazole은 처리농도가 높아질수록 토마토의 초장, 엽장, 엽면적 및 생체중을 감소시키고, chlorophyll 함량을 증대시켰으며 증산량을 현저히 감소시켰다. 오존처리는 증산량을 현저히 감소시켰으며 uniconazole 처리는 오존에 의한 증산량의 감소에 영향을 미치지 못하였다. 3. Uniconazole은 오존피해를 경감시킴으로 ethylene의 발생량을 크게 경감시켰으나 자엽의 낙엽 및 잎의 epinasty 발생을 방지시킬 수 없었다. 4. 오존처리는 POD의 활성을 크게 증가시켰으나, SOD의 활성은 감소시키는 경향이었다. Uniconazole은 농도가 높아짐에 따라 POD와 SOD의 활성을 약간 증가시키는 경향이었다. 5. Uniconazole을 처리한 다음 $GA_3$ 를 엽면살포한 결과 생장왜화효과가 소멸되면서 오존에 대한 내성도 감소되었다. 6. 이와같은 결과로 종합하여 볼 때, 토마토에 있어서 uniconazole의 오존 피해경감은 식물체의 왜화와 엽록소의 함량증대에 따른 오염물질의 세포 내 유입억제와 함께 oxyradical의 해를 중화시킬수 있는 요소의 활성증대가 일부 인정되는 것으로 판단된다.

• 대한화장품학회지
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• 제38권1호
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• pp.91-101
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• 2012

본 연구는 중앙아메리카의 폴리페놀 화합물로 이루어진 선바위고사리과에 속하는 양치식물 칼라구알라(Polipodium leucotomos)가 자외선 유해성으로부터 피부를 보호할 수 있는 항산화력과 활성 산소 유리기 농도를 알아보는데 그 목적을 두었다. 본 연구를 위하여 30대 이상 남녀 14명을 대상으로 4주 간 2개의 그룹으로 나누어 각각 칼라구알라와 위약을 섭취, 30 min 후 자외선에 노출되도록 하였다. 노출 후 3 h이 경과된 후에 각각 전완정맥에서 채혈하여 활성 산소 유리기(free oxygen radical) 농도와 총항산화능(total antioxidant capacity, TAC)을 비교 분석하여 다음과 같은 결과를 요약할 수 있었다. 첫째, 칼라구알라는 4주 후 활성 산소 유리기 농도를 유의하게 감소시켰고, 자외선 노출 30 min 후와 3 h 후의 활성 산소 유리기 농도는 위약군에 비해 유의하게 감소시키는 것으로 나타났다. 둘째, 칼라구알라는 4주 후 안정 시 총항산화능력을 유의하게 증가시키지 못하였지만, 자외선 노출 30 min 후와 3 h 후의 총항산화능력은 위약군에 비해 유의하게 감소시키는 것으로 나타났다. 사회가 급속도로 성장함에 따라 발생하는 대기오염, 각종 공해로 인하여 성층권에서 지속적으로 오존을 감소시켜 지상에 도달하는 유해 자외선량이 증가한다. 이는 활성화산소를 증가시켜 질병과 노화를 촉진시키는 요인이 된다. 기존의 반사와 산란작용으로 1차 피부를 차단하는 보호제외에도 칼라구알라와 같이 신체 내부에서 2차 차단을 할 수 있는 경구용 광항산화제의 연구가 계속적으로 이루어져야 할 것으로 사료된다.

• 농촌의학ㆍ지역보건
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• 제9권1호
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• pp.56-66
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• 1984

Giardia lamblia is a pathogenic flagellate causing intestinal disorders such as diarrhea, abdominal pain and malabsorption of nutrients. Giardia is mainly infected by the ingestion of contaminated foods per os. Craun (1979) has recently reported that mass infection of this flagellate through the contaminated water supply systems is one of public health hazards. Also, so-called traveller's diarrhea is sometimes caused by Giardia infection (CDC, U.S.A., 1971). However, a few epidemiological studies figuring out the mode of infection or control measures of Giardia infection has been done so far in Korea. The present study was aimed to know the prevalence of Giardia infection in several Korean populations, detectability of this flagellate in water systems and the viability of the cysts against sewages and disinfectants applying to drinking water. In the present study, 388 stool specimens from orphanage children in Chun-joo, Chung-joo, On-yang and Chun-an areas and 538 stool specimens from inhabitants in Woo-do, In-chon, and Chun-joo were examined by formalin-ether concentration technique to detect out Giardia cysts. On the other hand, water samples from 14 sites of Han River and its tributaries were collected in May through July, 1984. Fifty liter of water sample in each sampling site was then filtered through water filtering system deviced by U.S. Environmental Proutection Agency and the sediments rinsed out from the thread rolls, a part of water filtering system, were examined to detect out the Giardia cysts. In order to observe the viability of Giardia cysts in the sewage samples, the cysts were treated in it at $4^{\circ}C$ or $25^{\circ}C$ for 7 through 28 days. For this purpose, the cysts were also exposed to various concentrations of disinfectants such as chlorine, iodine and ozone gas for proper time intervals. After treatment, the viability test of the Giardia cysts were carried out by method of Rice and Schaefer (1981) with minor modification. The results obtained in this study were as follows : 1) The detection rates of G lamblia cysts in the stool specimens were 18.3% in orphans and 4.3% in general examinees. 2) The prevalences of Giardia Infection were higher in the young age groups than in-adults. The highest positive rate was 18.4% in the age group less than 10. 3) Of 14 water specimens sampled from Han River system and its tributaries around the Seoul area, the Giardia cysts were detected from 4 samples, and no cyst was found in the water supply systems. 4) The cysts treated in the sewage survived for 28 days at $4^{\circ}C$ and for 13 days at $25^{\circ}C$. 5) The cysts were completely destroyed within 60 minutes by exposure to 8 mg/l of residual chlorine at 4g and within 30 minutes by exposure to the same concentration of chlorine at $25^{\circ}C$. 6) The cysts were all dead when exposed to 1 mg/1 of iodine for 60 minutes at $4^{\circ}C$ or $25^{\circ}C$. 7) The cysts were destroyed after 10 minute exposure in 0.15 mg to 0.25mg of residual ozone gas per liter. Summarizing the above results, it is considered that Giardia infection is regarded as water-borne disease and the cysts are able to be controlled by the application with the disinfectants in the water supply systems.