• 한국환경보건학회지
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• 제39권6호
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• pp.505-512
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• 2013

Objectives: Ultraviolet (UV) radiation may cause skin cancer, photo-ageing, erythema, and sunburn. Benzophenone (BP) is commonly used to protect skin from UV radiation. In Korea, sunscreen, sunblock, socalled 'blemish balm' (BB) and 'color correcting' (CC) creams, and foundation may contain from 0.5 to 5% benzophenone in order to protect skin from UV radiation. The purpose of this study is to understand the levels of benzophenone derivatives in urine among a group of university students and identify the contribution of cosmetics use. Methods: Forty volunteers (20 women and 20 men) were asked about skin type, frequency of use of cosmetics, and recognition of related health effects, etc. in a survey. Subjects were divided into several subgroups and were compared for concentration of benzophenone-1 (BP-1) and benzophenone-3 (BP-3). Their urine was pretreated with enzyme hydrolysis and solid phase extraction. Determinations of BP-1 and BP-3 in the urine were made with LC-MS/MS. Results: Among the study subjects, 82.5% used basic cosmetics at least once per day, and 77.5% used sunscreens at least once per day. The concentrations of BP-1 and BP-3 of the males were 4.36 ng/mL and 9.16 ng/mL, respectively. Those of the females were 3.98 ng/mL and 5.07 ng/mL, respectively. The use of cosmetics was positively related to urinary benzophenone levels. Conclusions: BP-1 and BP-3 were widely detected among the university students. Cosmetic use was identified as a potential source. Implications of such exposure deserve further investigation.

• 한국농공학회지
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• 제19권4호
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• pp.4544-4554
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• 1977

The objective of this study was to measure and compare the radiation heat load generated through a few chosen shade-materials that would protect animals from the direct solar radiation heat in summer condition. The results obtained from this study are as follows; 1. when the materials were used in original state, the most effective material for radiation heat reduction was slate, followed by aluminum and galvanized steel successively. 2. The radiation heat load under the white top and black underside aluminum was 2.5 Cal. per hour per square cm less than that under the bare aluminum of their diurnal peak. 3. When the modified galvanized steel was used, the radiation heat load was reduced as much as 2.4 cal per hour per square cm by attaching plywood under the galvanized steel, 3.9 cal per hour per square cm by attaching plywood and coating white paint on the top of the galvanized steel. The galvanized steel covered by hay material showes similar result as that of the galvanized steel lined with plywood. 4. In case of slate, the radiation heat reduction value was increased by using bare slate, white top slate and white-top-black-underside slate in the descending order. 5. The calculated value of radiosity of inside surface of aluminum was about 20 percent of the radiation heat load, the reduced value of radiosity by coating paint was considered to be indirect indication of the effect of total radiation heat load reduction of painted surface. 6. About an hour of the time lag of radiation heat load peak on sept. 10 for slate materials should be investigated more comprehensively in future.

• 대한방사선치료학회지
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• 제19권2호
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• pp.83-90
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• 2007

목 적: 현재 시판되고 있는 맥주(Alcohol 4.5% 이하)를 섭취한 후에 인체가 방사선(X-선)에 노출되었을 경우 방어효과의 가능성여부를 확인하고자 한다. 대상 및 방법: 자원한 건강한 성인남자 5명(26$\sim$38세)으로부터 채취한 8 ml의 말초혈액 임파구세포를 분주하고 선형가속기를 이용하여 0.5 Gy, 1.0 Gy, 2.0 Gy, 3.0 Gy, 5.0 Gy의 방사선을 조사하고 맥주섭취 전과 후, 그리고 미량성분의 첨가후로 나누어 실험하였다. 방사선조사 후 60시간동안 이를 배양하고 세포고사(Apoptosis)된 세포군(Apoptosis group)을 정량적으로 분석하기 위하여 유세포 분석기(Flow cytometry)로 측정하였다. 결 과: 맥주섭취 전에 방사선조사로 유발된 세포고사 세포군(Apoptosis group)과 섭취 후 맥주에 의해서 억제된 세포고사 세포군을 서로 비교하였다. 맥주섭취 전 방사선에 유발된 세포고사(Apoptosis) 세포군(Apoptosis group)비율은 0.5 Gy, 1.0 Gy, 2.0 Gy, 3.0 Gy, 5.0 Gy에서 1.22$\pm$1.1, 1.38$\pm$1.0, 1.47$\pm$1.2, 1.47$\pm$1.1, 1.50$\pm$1.2로 선량에 따라 유의하게 증가하였으며, 맥주섭취 후 세포고사(Apoptosis)가 억제된 세포군(Apoptosis group) 비율은 선량에 따라서 0.97$\pm$1.2, 0.99$\pm$1.0, 1.11$\pm$0.9, 1.29$\pm$1.1, 1.15$\pm$1.1 으로 평균 약 21.4% 감소되었다. 또한 무알콜맥주에서 1.22$\pm$1.1, 1.17$\pm$1.1, 1.13$\pm$1.3, 1.38$\pm$1.2, 1.32$\pm$1.1으로 평균 10.8%로 저하된 것으로 분석되었다. 결 론: 인체가 방사선에 노출되기 전에 적당양의 맥주를 섭취하고 난 뒤에, 방사선에 노출된다면 맥주를 섭취하지 않은 상황에 비하여 방사선(X-선) 대한 방어효과(약 21.4%)가 일어남을 확인하였다.

• Nutrition Research and Practice
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• 제12권1호
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• pp.41-46
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• 2018

BACKGROUND/OBJECTIVES: Exposure of the normal lung tissue around the cancerous tumor during radiotherapy causes serious side effects such as pneumonitis and pulmonary fibrosis. Radioprotectors used during cancer radiotherapy could protect the patient from side effects induced by radiation injury of the normal tissue. Delphinidin has strong antioxidant properties, and it works as the driving force of a radioprotective effect by scavenging radiation-induced reactive oxygen species (ROS). However, no studies have been conducted on the radioprotective effect of delphinidin against high linear energy transfer radiation. Therefore, this study was undertaken to evaluate the radioprotective effects of delphinidin on human lung cells against a proton beam. MATERIALS/METHODS: Normal human lung cells (HEL 299 cells) were used for in vitro experiments. The 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay assessed the cytotoxicity of delphinidin and cell viability. The expression of radiation induced cellular ROS was measured by the 2'-7'-dicholordihydrofluorescein diacetate assay. Superoxide dismutase activity assay and catalase activity assay were used for evaluating the activity of corresponding enzymes. In addition, radioprotective effects on DNA damage-induced cellular apoptosis were evaluated by Western blot assay. RESULTS: Experimental analysis, including cell survival assay, MTT assay, and Western blot assay, revealed the radioprotective effects of delphinidin. These include restoring the activities of antioxidant enzymes of damaged cells, increase in the levels of pro-survival protein, and decrease of pro-apoptosis proteins. The results from different experiments were compatible with each to provide a substantial conclusion. CONCLUSION: Low concentration ($2.5{\mu}M/mL$) of delphinidin administration prior to radiation exposure was radioprotective against a low dose of proton beam exposure. Hence, delphinidin is a promising shielding agent against radiation, protecting the normal tissues around a cancerous tumor, which are unintentionally exposed to low doses of radiation during proton therapy.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.306-310
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• 2005

Exposure to UVB radiation can cause diverse biological photodamage to skin. Eeb 761 and Korean red ginseng are the major and most effective natural drug against a variety of oxidative damage. But, the protective effects against UVB radiation have not been clearly identified. In this study, we investigated the protective effect of topical EGb 761 and Korean red ginseng on pigmentation by UVB radiation. Pro-inflammatory cytokines($IL-l{\beta}$, IL-6 and $TNF-{\alpha}$) and melanogenesis proteins(tyrosinase, TRP-1 and TRP-2) mRNA were measured by reverse transcription-polymerase chain reaction(RT-PCR) analysis. The in vivo protection against pigmentation was calculated using chromameter. The mRNA level of IL-lf and TNF-a were increased by UVB irradiation in treated and non-treated group, while no significant changes were observed in IL-6 level. Topical treatment with EGb 761 and Korean red ginseng remarkably reduced expression of tyrosinase, TRP-1 and TRP-2 in the non-irradiated and irradiated skin. Application of EGb 761 and Korean red ginseng significantly protected the WB-induced skin pigmentation and Korean red ginseng was more effective. Our study suggests that topical ECb761 and Korean red ginseng can regulate melanogenic proteins and protect UVB radiation on skin pigmentation.

• 한국식품영양학회지
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• 제29권6호
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• pp.829-834
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• 2016

Free radicals originate due to the radiolysis of cytoplasmic water with low "Linear Energy Transfer" (LET) radiations. Naringenin (Ng) is a natural antioxidative compound found in citrus fruits. This study revealed that Naringenin (Ng) reduced the radiation damage of critical organs by scavenging oxidative free radicals. In the study, Ng was orally administrated to rats daily for 7 consecutive days, prior to whole body exposure to gamma-rays. The scavenging efficacy was evaluated biochemically by measuring the concentration of cytotoxic byproducts and the activity of enzymes relevant to oxidative free radicals, after extracting the organs from the exposed rat. We observed increased levels of malondialdehyde (MDA) concentration, and decrease in the activities of superoxide dismutase (SOD) and catalase (CAT) in the exposed control group. However, pretreatment with Ng significantly reduced the MDA concentration, and increased the activities of SOD and CAT, as compared to the control group, due to the free radical scavenging by Ng. The results indicate that Ng administration prior to irradiation could protect critical organs from radiation damage.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.526-531
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• 2011

A dash panel component, close to passengers, plays a very important role to protect heat and noise from a power train. Meanwhile, it is also a main path that transfers vibration energy and eventually radiates acoustic noise into the cavity. Therefore, it seems important to provide an optimal design scheme incorporating sound packages such as dash isolation pad and carpet, as well as structures. The present study is the extension of the previous investigation how design variables affect sound radiation, which was carried out using the simple plate and framed system. The system taken into account in this paper is a dash panel component of a sedan, which includes A pillar, front side member, dash panel and the corresponding sound packages. Design variables such as panel thickness and sound package layers are investigated how they are related for the better radiation performance (i.e. structure-borne) and sound transmission loss (i.e. air borne).

• Nuclear Engineering and Technology
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• 제49권8호
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• pp.1772-1777
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• 2017

Korean nuclear power plants (NPPs) periodically evaluate the radioactive gaseous and liquid effluents released from power reactors to protect the public from radiation exposure. This paper provides a comprehensive overview of the release of radioactive effluents from Korean NPPs and the effects on the annual radiation doses to the public. The amounts of radioactive effluents released to the environment and the resulting radiation doses to members of the public living around NPPs were analyzed for the years 2011-2015 using the Korea Hydro & Nuclear Power Co., Ltd's annual summary reports of the assessment of radiological impact on the environment. The results show that tritium was the primary contributor to the activity in both gaseous and liquid effluents. The averages of effective doses to the public were approximately on the order of $10^{-3}mSv$ or $10^{-2}mSv$. Therefore, even though Korean NPPs discharged some radioactive materials into the environment, all effluents were within the regulatory safety limits and the resulting doses were much less than the dose limits.

• 한국해양공학회지
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• 제33권4호
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• pp.330-339
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• 2019

Radiant heat shields are normally installed on offshore oil and gas platforms to protect personnel, equipment, and structures from the thermal radiation emitted by a flare system. A heat shield should be individually designed to reduce the thermal radiation to the target level, and then manufactured and installed after the performance verification. However, in general, a heat shield is designed and manufactured by trial and error based on the performance test. For this reason, it is difficult to develop and design radiant heat shields in the Korean shipbuilding and marine equipment industry because of the lack of performance test data and limited experience. In the present study, the results of experiments conducted to verify the performances of radiant heat shields were analyzed, and the thermal radiation characteristics and performance characteristics of the radiant heat shields were investigated. The insights and conclusions developed in the present study will be useful in terms of the design and development of radiant heat shield, as well as in their performance verification tests.

• 의료법학
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• 제14권2호
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• pp.119-142
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• 2013

It is not easy to regulate the amount of radiation used for the medical purpose as there usually is more good than harm to the patient's health and life caused by the medical exposure to the radiation. However, the rapid increase of the use of diagnostic radiation involves a high possibility of increasing the radiation hazard exposure. Therefore, it is imperative to implement effective regulations in order to secure the safety of diagnostic radiation. The one and only rule we currently have for the diagnostic radiation is "Medicine Act" with only one clause dedicated to regulate the safety management that does not include any rules for the medical radiation. A set of inclusive rules for the whole medical radiation inclusive of diagnostic radiation and therapeutic radiation need to be based on the "Medicine Act" rather than "Nuclear Safety Act" in order to protect the medical professionals, patients and the guardians of patients from the hazards of diagnostic and/or therapeutic radiation that was not used the purpose of medical treatment. If there is an administrative measure to be imposed to secure the safety of diagnostic radiation, it is considered as exertion of governmental authority of administrative agency. There must be clear and realistic legal guidelines for in-fringe on people's interests. The administrative measures for the safety management of the diagnostic radiation must be clearly and specifically based on the law and the detailed standards for the administrative measures must be dele-gated by the presidential decree or departmental ordinance. Accordingly, the restrictions imposed by the administrative measures to the "Safety Inspection Institute of Radiation along with Radiation Exposure Measuring Institutes" should have clear legal basis as well and the detailed standards for the administrative measures should be regulated by the Ministry of Health and Welfare decree instead of the notification by the Director of Korean Centers for Disease Control and Prevention. While securing the safety of radiation on one side, careful review and up-grade on our legal system for the safety management of the diagnostic radiation is required on the other side to guarantee the legality, interest balance and reliability of the administrative measures.