• 한국화재소방학회논문지
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• 제32권2호
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• pp.1-6
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• 2018

붕산과 5붕산암모늄으로 처리한 편백나무 시험편의 연소특성에 관한 실험을 ISO 5660-1 표준에 따른 콘칼로리미터를 이용하여 수행하였다. 그 결과 붕산과 5붕산암모늄의 혼합된 투여는 그들의 시너지 효과에 의해 화재성능지수 값을 향상시켰다. 또한 붕소 화합물로 처리한 시험편은 공시편보다 총열방출율 값이 6.1~14.1% 감소되었다. 붕소화합물로 처리된 시편의 총연기방출율은 연소과정 전반에 걸쳐 감소되었으나 붕산/5붕산암모늄은 예외였다. 일산화탄소 최대농도는 15.8~25.5% 정도 감소하는 경향성이 있었다. 대체적으로 난연제로 처리한 목재는 화재 위험성이 낮아진 것으로 이해된다.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.153-159
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• 2010

Perfluorooctane sulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA) are the principal chemicals known as perfluoroalkyl acids (PFAs). Despite the widespread use of these compounds, relatively little is known about their fate and effects. The purpose of this study was to determine the toxic effects of PFOS and PFOA on Daphnia magna. In the acute toxicity test, D. magna were exposed for 48 hours at concentrations of 0, 30, 45, 67.5, 101.25 and 151.88 mg/L PFOS, and 0, 100, 160, 225, 337.5 and 506.25 mg/L PFOA, respectively. In the case of chronic toxicity test, D. magna were exposed through water for 21 days at concentrations of 0, 0.375, 0.75, 1.5, 3 and 6 mg/L PFOS, and 0, 1.25, 2.5, 5, 10 and 20 mg/L PFOA, respectively. Acute toxicity was assessed on the basis of immobility, while chronic toxicity was assessed on the basis of fecundity. The acute toxicity test on PFOS and PFOA showed that the values of $EC_{50}$ were 50.90 mg/L and 253.47 mg/L, respectively. In the chronic test, fecundity was reduced significantly at 1.5 mg/L of PFOS and 10 mg/L of PFOA, respectively. These results indicated that PFOS is more toxic to zooplankton than PFOA, and both chemicals have some hazard demonstrates risk for acute or chronic toxicity to freshwater organism.

• Molecular & Cellular Toxicology
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• 제1권2호
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• pp.73-77
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• 2005

Nickel is the one of potent environmental, the occupational pollutants and the classified human carcinogens. It is a serious hazard to human health, when the metal exposure. To prevent human diseases from the heavy metals, it is seemingly important that understanding of how nickel exerts their toxicity and carcinogenic effect at a molecular and a genomic level. The process of nickel absorption has been demonstrated as phagocytosis, iron channel and diffusion. Uptaked nickel has been suggested to induce carcinogenesis via two pathways, a direct DNA damaging pathway and an indirect DNA damaging pathway. The former was originated from the ability of metal to generate Reactive Oxygen Species (ROS) and the reactive intermediates to interact with DNA directly. Ni-generated ROS or Nickel itself, interacts with DNAs and histones to cause DNA damage and chromosomal abnormality. The latter was originated from an indirect DNA damage via inhibition of DNA repair, or condensation and methylation of DNA. Cells have ability to protect from the genotoxic stresses by changing gene expression. Microarray analysis of the cells treated with nickel or nickel compounds, show the specific altered gene expression profile. For example, HIF-I (Hypoxia-Inducible Factor I) and p53 were well known as transcription factors, which are upregulated in response to stress and activated by both soluble and insoluble nickel compounds. The induction of these important transcription factors exert potent selective pressure and leading to cell transformation. Genes of metallothionein and family of heat shock proteins which have been known to play role in protection and damage control, were also induced by nickel treatment. These gene expressions may give us a clue to understand of the carcinogenesis mechanism of nickel. Further discussions on molecular and genomic, are need in order to understand the specific mechanism of nickel toxicity and carcinogenicity.

• 환경생물
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• 제18권3호
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• pp.291-298
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• 2000

난황형성(vitellogenesis)은 난생동물의 번식에서 매우 중요한 과정으로 간에서 난황전구물질(vitellogenin,Vg)의 생성과 단백질 수준에서 Vg의 변형과 난자내 축적 및 난황물질(vitellin)로의 전환을 포함한다. 난황은 경골어류의 배아의 영양물질 및 삼투압 조절을 통한 부유특성의 조절에 관여한다. 척추동물의 Vg유전자는 lipoprotein계열의 유전자로 복수의 Vg유전자가 존재하며 서로 다른 크기의 Vg단백질을 암호화한다. 에스트로젠에 의해 이들 단백질이 발현되는 정도에는 차이가 있다. 난생 척추 동물의 암컷에서 에스트로젠의 조절하에 생성되는 Vg은 천연 에스트로젠 및 합성에스트로젠에 의해 어류, 양서류, 파충류, 조류 등 다양한 척추동물의 수컷 체내에서도 형성되며 수온 및 생식주기에 의존적이다. 따라서 수컷에서 일어나는 난황전구물질의 생성은 환경오염물질 가운데 여성호르몬과 유사한 작용을 하는 물질의 규명과 위해성 여부를 판정할 수 있는 생물학적 지표로서 전세계적으로 이용되고 있다. 국내의 경우 Vg유도여부를 통한 야생생태계에서 환경호르몬 오염과 동물의 번식장애에 대한 연구에 있어서 번식주기, 동물의 지리적 분포와 생물다양성의 차이에 대한 고려가 중요하다.

• 대한약침학회지
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• 제25권2호
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• pp.121-129
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• 2022

Objectives: The chemical composition of cactus pear seed oil (Opuntia ficus-indica [L.] Mill.) was analyzed in terms of its fatty acid composition, tocopherol content, phenolic identification, and the oil's phenolic-rich fraction antioxidant power was determined. Methods: Fatty acid profiling was performed by gas chromatography coupled to an FI detector. Tocopherols and phenolic compounds were analyzed by LC-FLD/UV, and the oil's phenolic-rich fraction antioxidant power was determined by phosphomolybdenum, DPPH assay and β-carotene bleaching test. Results: Fatty acid composition was marked by a high unsaturation level (83.22 ± 0.34%). The predominant fatty acid was linoleic acid (66.79 ± 0.78%), followed by oleic acid (15.16 ± 0.42%) and palmitic acid (12.70 ± 0.03%). The main tocopherol was γ-tocopherol (172.59 ± 7.59 mg/kg. In addition, Tyrosol, vanillic acid, vanillin, ferulic acid, pinoresinol, and cinnamic acid were identified as phenolic compounds in the analyzed seed oil. Moreover, the oil's phenolics-rich fraction showed a significant total antioxidant activity, scavenged DPPH up to 97.85%, and effectively protected β-carotene against bleaching (97.56%). Conclusion: The results support the potential use of cactus pear seed oil as a functional food.

• Advances in environmental research
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• 제1권4호
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• pp.277-288
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• 2012

This study investigated exposure to air pollutants in rooms in low-income houses at Shomolu (R1), Mafoluku (R2) and Mushin (R3) in Lagos state. The concentrations of most measured exceeded limits of Illinois Department of Public Health (IDPH) for indoor air quality. Air quality index (AQI) in rooms studied was unhealthy for sensitive people in terms of CO, unhealthy in terms of $SO_2$ and very unhealthy in terms of $NO_2$ while moderate air quality was obtained in terms of $PM_{10}$ in most rooms. High concentrations of carbontetrachloride, formaldehyde and xylene measured could have been responsible for some of the health complaints of the occupants. Factor analysis shows that cooking with kerosene, use of gasoline generator and insecticide were the major contributors to indoor air pollution in these rooms. Therefore, there is need to urgently tackle poverty as all affected by these pollutants were poor who live in substandard houses without kitchens.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4185-4197
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• 2016

Chronic arsenicosis is a major environmental health hazard throughout the world, including India. Animals and human beings are affected due to drinking of arsenic contaminated ground water, due to natural mineral deposits, arsenical pesticides or improperly disposed arsenical chemicals. Arsenic causes cancer with production of free radicals and reactive oxygen species (ROS) that are neutralized by an elaborate antioxidant defense system consisting of enzymes and numerous non-enzymatic antioxidants. Dietary antioxidant supplements are useful to counteract the carcinogenesis effects of arsenic. Oyster mushroom lectins can be regarded as ingredients of popular foods with biopharmaceutical properties. A variety of compounds have been isolated from mushrooms, which include polysaccharides and polysaccharopeptides with immune-enhancing effects. Lectins are beneficial in reducing arsenic toxicity due to anticarcinogenetic roles and may have therapeutic application in people suffering from chronic exposure to arsenic from natural sources, a global problem that is especially relevant to millions of people on the Indian subcontinent.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.515-517
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• 2003

In order to assess the risk of adverse health effects on human exposure to arsenic and heavy metals influenced by past mining activities, environmental geochemical surveys were undertaken in the abandoned metal mine areas (Dongil Au-Ag-Cu-Zn, Okdong Cu-Pb-Zn, Songcheon Au-Ag, Dongjung Au-Ag-Pb-Zn, Dokok Au-Ag-Cu and Hwacheon Au-Ag-Pb-Zn mines). Arsenic and other heavy metals were highly elevated in the tailings from the Dongil, the Songcheon and the Dongjung mines. High concentrations of heavy metals except As were also found in tailings from the Okdong, the Dokok and the Hwacheon mines. These significant concentrations can impact on soils and waters around the tailing dumps. Risk compounds deriving from mine sites either constitute a toxic risk or a carcinogenic risk. The hazard index (H.I.) of As in the Dongil, the Okdong, the Songcheon and the Hwacheon mine areas was higher value more than 1.0. In the Okdong and the Songcheon mine areas, H.I. value of Cd exceeded 1.0. These values of As and Cd were the highest in the Songcheon mine area. Therefore, toxic risks for As and Cd exist via exposure (ingestion) of contaminated soil, groundwater and rice grain in these mine areas. The cancer risk for As in stream or ground water used for drinking water from the Songcheon, the Dongil, the Okdong, the Dongjung and the Hwacheon mine areas was 3E-3, 8E-4, 7E-4, 2E-4 and 1E-4, respectively.

• 한국대기환경학회지
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• 제8권2호
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• pp.100-104
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• 1992

본 연구는 비교 위험도 평가 기법을 사용하여, 도시 고형 폐기물의 소각에 따른 대기 오염 중 발암성 금속이 호흡기를 통해 소각로 주변 주민에게 미치는 암 위험도를 다옥신과 비교해 평가하였다. 어떤 물질이 인체에 암을 유발할 가능성이 있는 경우, 이 발암성은 물질의 화학적 형태 및 피폭경로에 관련될 지도 모른다. 물질의 발암성에 대한 이러한 사실이 조사되었고 위험도 정량화에 고려되었다. 본 연구 결과, 도시 고형 폐기물의 소각시 방출되는 발암성 금속으로 인한 위험도는 디옥신으로 인한 위험도의 약 5배 정도로 평가되었고, 위험도의 측면에서 가장 중요한 금속은 6가 크롬과 카드뮴인 것으로 판명되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.495-495
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• 2011

Miniaturized sensors capable of both sensitive and selective real-time monitoring of target analytes are tremendously valuable for various applications ranging from hazard detection to medical diagnostics. The wide-spread use of such sensors is currently limited due to insufficient selectivity for target molecules. We developed selective nanocoatings by combining trinitrotoluene (TNT) receptors bound to conjugated polydiacetylene (PDA) with single-walled carbon nanotube-field effect transistors (SWNT-FET). Selective binding events between TNT molecules and phage display derived TNT receptors were effectively transduced to sensitive SWNT-FET conductance sensors through the PDA coating. The resulting sensors exhibited unprecedented 1 fM sensitivity toward TNT in real time, with excellent selectivity over various similar aromatic compounds. Our biomimetic receptor coating approach may be useful for the development of sensitive and selective micro and nanoelectronic sensor devices for various other target analytes.