• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.165-172
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• 2020

Heavy metals are common pollutants in the freshwater environment and have toxicological effect in habitat organisms. The heavy metals highly accumulated in sediment and organism, and observed various physiological responses. In this study, we investigated the molecular response to heavy metal toxicity (Al, Aluminum; Cr, Chromium; Cu, copper; Mn, Manganese; Zn, Zinc) through expression of heat shock protein 40, 70, 90 (HSP40, 70, 90), cytochrome 450 (CYP450), Glutathione S-transferase (GST) and Serine-type endopeptidase (SP). HSPs showed up-regulation in Cu and Zn exposures. Furthermore, HSPs expression in treated groups tended to be higher than the control group. The tendency of CYP450 and GST mRNA expression was higher for Cr and Cu than for other exposure group. The expression of SP gene was low at Al exposure and other group were measured to be similar to control. These results suggest that heavy metal toxicity in freshwater ecosystem may affect physiological and molecular process. Also, the comprehensive gene expression in the aquatic midge Chironomus riparius give useful information to potential molecular biomarkers for assessing heavy metal toxicity.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.87-100
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• 2003

It is important to understand the potential human health implications of exposure to environmental chemicals that may act as hormonally active agents. It is necessary to have an understanding of how pharmaceutical and personal care products and other chemicals affect the ecosystem of our planet as well as human health. Endocrine disruption is defined as the ability of a chemical contaminating the workplace or the environment to interfere with homeostasis, development, reproduction, and/or behavior in a living organism or it's offspring. Certain classes of environmentally persistent chemicals such as polychlorinated biphenyls (PCBs), dioxins, furans, and some pesticides can adversely effect the endocrine systems of aquatic life and terrestrial wildlife. Research continues to support the theory of endocrine disruption. However, endocrine disruption researches have been applied to proteomics poorly. Proteomics can be defined as the systematic analysis of proteins for their identity, quantity and function. It could increase the predictability of early drug development and identify non-invasive biomarkers of tonicity or efficacy. Proteome analysis is most commonly accomplished by the combination of two-dimensional gel electrophoresis (2D/E) and MALDI-TOF mass spectrometry (MS) sr protein chip array and SELDI-TOF MS. Proteomics have an opportunity to play an important role in resolving the question of what role endocrine disruptors play in initiating human disease. Proteomics can also play an imfortant role in the evaluation of the risk assessment and use of risk management and risk communication tools required to address public health concerns related to notions of endocrine disruptors. Understanding the need for the proteomics and possessing knowledge of the developing biomakers used to abbess endocrine activity potential will he essential components relevant to the topic of endocrine disruptors.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.111-123
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• 2009

We investigated the consumption inclinations of consumers for environmentally-friendly agricultural products (EFAP) for better production and distribution of EFAP. Consumer inclinations in large supermarkets from April 7th to 30th, 2008 were surveyed. Data were analyzed using the SPSSWIN 12.0 program. Results showed that 90.4% of consumers recognized EFAP and 76.4% of those who recognized the products had actually bought the products. Members of the "have purchased group" bought EFAP once a week because they believed these products were safe from hazards, such as pesticide. The amount spent on EFAP was less than 20% of the total food budget and the major consumed items were green vegetables and fruits. The sale location was mainly large supermarkets and agricultural cooperation outlets. Although many people were satisfied with EFAP from the viewpoint of nutritional and sensory qualities and safety compared with general agricultural products, they were notsatisfied with the price. Many consumers trusted that EFAP were safe and nutritional. Members of the "not purchased group" also trusted the nutritional and sensory qualities of EFAP and recognized the safety issue, but they were not satisfied with the price, compared with general agricultural products. Consequently, to succeed in the market, EFAP should maintain the confidence of the consumer while decreasing in price.

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.407-420
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• 2000

삼차신경절의 뉴런이 구강악안면영역에서의 촉각, 입각, 온도각 및 통각 등 다양한 감각을 중추신경계로 전달하는 역할을 하는 것은 주지의 사실이다. 이러한 신경전달에 있어서 이온통로는 감각정보를 전달하는데 핵심적인 역할을 수행하며 특히 소디움 통로는 활동전위의 발생에 중요하다. 소디움 통로는 tetrodotoxin-sensitive(TTX-s) 및 tetrodotoxin-resistant(TTX-r) 통로로 나누어지는 데 이 중 TTX-r 통로에 발생되는 tetrodotoxin-resistant sodium current(TTX-r $I_{Na}$)는 capsaicin에 민감한 일차구심신경세포에서 유해자극에 의해 통각신호를 발생시키고 전달하는데 중요하다. 또한 칼슘 통로는 시냅스 전도에 있어서 필수적인 역할을 수행하고 있다 한편 치과영역에서 치수의 진정 목적으로 eugenol이 흔히 사용되고 있다. 그러나 eugenol의 그 작용 기전에 대해서 현재까지 이온 통로에 대한 상세한 결과가 없는 실정이며 최근의 보고에 의하면 eugenol이 capsaicin 수용기를 통하여 감각신경에 대한 억제작용을 나타낸다고 한다. 따라서 본 실험은 eugenol과 capsaicin이 흰쥐의 삼차신경절의 TTX-r $I_{Na}$와 칼슘통로에 어떠한 영향을 미치는지를 알아보고 eugenol이 capsaicin 수용기를 통하여 작용하는지를 검증하고자 시행되었다. 삼차신경절 뉴런은 100~150g의 흰쥐의 삼차신경절로부터 외과적으로 절제하여 통법의 화학적 및 기계적 처리를 통해 단일세포로 분리하였고 이를 whole-cell patch clamp 방법을 이용하여 시행한 바 다음과 같은 결론을 얻었다. 1. 1mM의 dugenol은 흰쥐 삼차신경절 뉴런의 TTX-r $I_{Na}$와 HVA $I_{Ca}$를 억제하였다. 2. $1{\mu}m$의 capsaicin은 흰쥐 삼차신경절 뉴런의 TTX-r $I_{Na}$와 HVA $I_{Ca}$를 억제하였다. 3. Capsazepine은 capsaicin의 HVA $I_{Ca}$에 대한 억제작용을 차단하였다. 4. Capsazepine은 capsaicin의 HVA $I_{Ca}$에 대한 억제작용을 차단하지 못하였다. 결론적으로 eugenol과 capsaicin은 tetrodotoxin-resistant sodium current(TTX-r $I_{Na}$)와 high voltage-activated calcium current(HVA $I_{Ca}$)를 모두 억제하는 것으로 나타났으며, 이러한 작용이 통각의 발생과 시냅스 전달과정을 차단하여 치수 진정 목적으로 많이 사용하는 eugenol의 작용기전으로 판단된다. 한편 capsaicin의 길항제인 capsazepine을 전처치하였을 때에도 eugenol의 HVA $I_{Ca}$에 대한 억제효과는 변화가 없었다. 이와같은 결과로 보아 HVA $I_{Ca}$에 관한 한 eugenol은 capsaicin 수용기를 통하여 나타나지 않는 것으로 사료된다.

• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.679-688
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• 2013

This study figured out the influential factors of region-based characteristic factors in our country upon asthmatic occurrence. Research subjects were 2,266,451 people who were confirmed the diagnosis of asthma (J45~J46) among patients in national health insurance for the year in 2010. The influence in each of factors upon the asthmatic occurrence was analyzed through hierarchical regression after comparing difference in asthmatic occurrence by basic local government. As a result of hierarchical regression, the whole asthmatic occurrence had significant difference in infants ratio, $SO_2$,Temperature, basin and dam area. The asthmatic occurrence had significant difference in subjective awareness of health level, $SO_2$, basin and dam area. A case of asthmatic occurrence had significant difference in infants ratio, temperature, $NO_2$ and coastal area. Diverse characteristic factors by region were indicated to have influence upon the asthmatic occurrence by causing or weakening asthma through mutually complex action. Accordingly, a region-based customized environmental health measure will need to be arranged that infants and elderly people, who are vulnerable classes, can be protected and prevented from harmful environment of asthma.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.538-545
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• 2020

The outdoor coal storage sheds of thermal power plants are being converted to indoor coal storage sheds worldwide because of the environmental pollution problems in the surrounding areas. On the other hand, indoor coal storage sheds are causing problems, such as indoor coal scattering and harmful gas generation. In this study, the ventilation method of indoor coal storage sheds was analyzed in terms of the internal flow characteristics and ventilation according to the outside wind velocity and direction. CFD analysis was performed based on the actual flow measurement information inside the indoor coal storage sheds. A comparison of the wind speed of 6 m/s and 2 m/s when the outside wind direction was easterly showed that the stream velocity to the monitor louver was faster and the recirculation area was clearer at 6 m/s than at 2 m/s. In addition, the trend of a westerly wind was similar to that of the easterly wind. The ventilation rate according to the wind speed was 13.1 times and 4.4 times for a wind speed of 6 m/s and 2 m/s, respectively. If the wind speed is 2 m/s, the situation does not meet the required number of ventilations per hour in a general plant, and needs to be improved.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.91-97
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• 2007

A survey of risk perception in Korea was conducted in 2001 with a special emphasis on industrial and technological risks. This article summarizes the characteristics of risk perception in consideration of socio-demographic background of respondents. The survey with sample size of 1,870 evaluates the perceived level of 25 risk items in the areas of transportation, chemicals, environment, industry, and nuclear power generation. Risks are categorized by using factor analysis to clarify attitudinal or behavioral properties of risk perception. Research findings show that the level of perceived risk does not correspond to the statistical level. Socio-demographic variables are significant predictors in explaining risk perception, or the discrepancies between "subjective" and "objective" risks. Effective risk communication can reduce the perceptional discrepancies, improve the awareness of technological risks, and ultimately facilitate the process of making and implementing policies for risk management and safety regulation. This article tries to provides policy guidelines for "Who is the target for risk communication" and "Which risk has the policy priority for safety improvement." Married females at the age of 30s and 40s with lower education and lower income in small cities are more vulnerable to risk misperception than other groups. More information and knowledge regarding unfamiliar, intangible, new technological risks should be delivered to the vulnerable groups for reducing perceptional bias. Society-wide safety can be improved by integrating policy, human, and social factors as well as techno-engineering advances.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.116-116
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• 2007

21 세기에 접어들면서 인터넷을 통한 정보 통신의 발달과 개인 휴대용 이동 통신기기의 활발한 보급에 따라 휴대형 전자기기들의 소형화와 고성능화로 나아가고 있다. 이러한 전자기기에 사용될 IC의 내장 메모리 또한 집적화 및 고속화, 저 전력화가 이루어져야 한다. 이러한 전자기기들에 필수적인 압전 세라믹스 부품 중 압전 부저 및 기타 음향 부품등을 각종 전자기기와 무선 전화기에 채택함으로써 압전 부품에 대한 수요와 생산이 계속 증가할 것으로 전망된다. 이처럼 압전 세라믹스를 이용한 그 응용 범위는 대단히 방대하며, 현재 모든 압전 부품들은 PZT 계열 재료로 만들어지고 있고, 차후 모두 비납계열 재료로 대체될 것이 확실시된다. Pb의 환경오염은 이미 오래전부터 큰 문제점으로 인식되고 있었으며 그 일례로 미국의 캘리포니아 주에서는 1986년부터 약 800종의 유해물질, 그 중에서도 Pb 사용을 300ppm 이하로 규제하는 Proposition 65를 제정하여 실행하고 있다. 그리고 2003년 2월에 EU (European Union) 에서 발표한 전자산업에 관한 규제 사항중 하나인 위험물질 사용에 관한 지칭 (Restriction of Hazardous Substance, RoHS) 에 의하면, 2006 년 7월부터 전기 전자 제품에 있어서 위험 물질인 Pb을 포함한 중금속 물질(카드늄, 수은, 6가 크롬, 브롬계 난연재)의 사용을 금지한다고 발표하였다. 비록 전자세라믹 부품에 함유된 Pb는 예외 사항으로 두었지만 대체 가능한 물질이 개발되면 전자세라믹 부품에서도 Pb의 사용을 금지한다고 규정하였다. 더욱이 일본은 2005 년부터 Pb 사용을 금지시켰다. 이와 같이 Pb가 환경에 미치는 영향 때문에 비납계 강유전 물질 및 압전 세라믹스 재료에 대한 연구가 전 세계적으로 활발히 진행되고 있다. 본 연구에서는 비납계 강유전체의 patterning을 위해서, NKN 박막을 고밀도 플라즈마원인 ICP를 이용하여 식각 mechanism을 연구하고, 식각변수에 따른 식각 공정을 최적화에 대하여 연구하였다. 가스 혼합비에 따라 식각 할때 700 W의 RF 전력과 - 150 V의 직류 바이어스 전압을 인가하였고, 공정 압력은 2 Pa, 기판 온도는 $23^{\circ}C$로 고정하였다. 식각 속도는 Tencor사의 Alpha-step 500을 이용하여 측정되었으며 식각 시 NKN 박막 표면과 라디칼과의 화학적인 반응을 분석하고 식각 메커니즘을 규명하기 위하여 XPS(x-ray photoelectron spectroscopy)를 사용하였다.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.136-143
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• 2018

Cellular automata have been applied to simulations in many fields such as astrophysics, social phenomena, fire spread, and evacuation. Using cellular automata, this study develops a model for consequence analysis of the dispersion of hazardous chemicals, which is required for risk assessments of and emergency responses for frequent chemical accidents. Unlike in cases of detailed plant safety design, real-time accident responses require fast and iterative calculations to reduce the uncertainty of the distribution of damage within the affected area. EPA ALOHA and KORA of National Institute of Chemical Safety have been popular choices for these analyses. However, this study proposes an initiative to supplement the model and code continuously and is different in its development of free software, specialized for small and medium enterprises. Compared to the full-scale computational fluid dynamics (CFD), which requires large amounts of computation time, the relative accuracy loss is compromised, and the convenience of the general user is improved. Using Python open-source libraries as well as meteorological information linkage, it is made possible to expand and update the functions continuously. Users can easily obtain the results by simply inputting the layout of the plant and the materials used. Accuracy is verified against full-scale CFD simulations, and it will be distributed as open source software, supporting GPU-accelerated computing for fast computation.

• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.547-555
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• 2018

In addition to North America and Europe, Korea is also responding to the toxic damage caused by the production and distribution of chemicals. Methods for assessing bio-toxicity of harmful substances have been widely introduced, but it is required of quantitative and speedy information for modeling. For 6 heavy metals, as zinc, copper, chrome, cadmium, mercury and lead, bio-toxicity assessment and kinetics model were constructed using Vibrio fischeri which is widely used luminous bacteria. The degree of luminescence activity and the toxicity of heavy metals were relative limunescence unit, RLU measured as by using a photomultiplier embedded device. The toxicity was assessed by the concentration levels giving under 20% lethality and lethal concentration, $EC_{50}$. In the results, the toxicity order were followed from mercury, lead, copper, chrome, zinc and cadmium. $EC_{{50},{\infty}}$ obtained by trends of $EC_{50}$ by time follows had highly linear agreement with main parameters of bio-toxicity modelling. The average error rates of the reproduced lethality obtained from DAM and TDM model on the basis of body residue, were 10.2% for mercury, lead, copper, chrome and 20.0 for the all 6 methals.