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A Study on the Variation of the Concentrations of Carbon Species and B(a)P Associated in Atmospheric Suspended Particles in an Urban Area of Seoul (서울지역 일부 대기중 부유먼지에 함유된 탄소 성분과 Benzo(a)pyrene 성분의 농도변동 양상에 관한 연구)

  • 황경철;김희강
    • Journal of Environmental Health Sciences
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    • v.23 no.4
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    • pp.91-96
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    • 1997
  • In order to investigate the behavior of particulate carbon and benzo(a)pyrene(B(a)P) in the ambient air, suspended particle matters were collected from April, 1990 to February, 1992, and total carbon(TC), organic carbon(OC), elemental carbon(EC) and B(a)P were measured by an elemental analyzer and a HPLC. The results were as follows the average concentration of TC was 38.6 $\mug/m^3$ and its concentration was higher in winter(45.4 $\mug/m^3$) and fa11(44.3 $\mug/m^3$) than in summer(36.8 $\mug/m^3$) and spring(28.9 $\mug/m^3$). The monthly concentration trends both of EC and OC was similar, but seasonal variation of EC concentrations was larger than that of OC. The average concentration of B (a)P was 2.2 ng/m$^3$, and was higher in winter(4.1 ng/m$^3$) and fall(3.2 ng/m$^3$) than in spring(1.2 ng/m$^3$) and summer(0.6 ng/m$^3$). The seasonal behavior of carbon and B(a)P was to similar except for summer. The correlation coefficient(r) between EC and B(a)P was 0.71, and the correlation coefficient(r) between OC and B(a)P was 0.66.

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Discharge Characteristics of Indicator Microorganisms from Agricultural-Forestry Watersheds (농지-임야에서 발생하는 지표미생물 유출 특성)

  • Kim, Geonha
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.1B
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    • pp.153-160
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    • 2008
  • To estimate microbial contaminant loading discharged from diffuse sources, rainfall runoff of six rainfall events were monitored at three study watersheds of forestry and agricultural land use. Monitored indicator microorganism constituents were total coliform (TC), fecal coliform (FC), Escherichia coli (EC), and fecal streptococcus (FS). Soil loss during elevated flow rate caused higher suspended solid concentrations. Indicator microorganism concentrations were closely related with flow rate. TC event mean concentration (EMC) from unpolluted forestry was $5.3{\times}10^3CFU/100ml$, FC EMC was $1.4{\times}10^3CFU/100ml$, EC EMC was $1.1{\times}10^3CFU/100ml$, and FS EMC was $2.9{\times}10^2CFU/100ml$. From a watershed with agricultural-forestry land use, TC EMC was $1.7{\times}10^5CFU/100ml$, FC EMC was $8.5{\times}10^4CFU/100ml$, EC EMC was $8.9{\times}10^4CFU/100ml$, and FS EMC was $3.4{\times}10^4CFU/100ml$. Mixed land use of agricultural-forestry with bigger area, TC EMC was $1.9{\times}10^5CFU/100ml$, FC EMC was $9.6{\times}10^4CFU/100ml$, EC EMC was $7.0{\times}10^4CFU/100ml$, and FS EMC was $5.1{\times}10^4CFU/100ml$.

Acute Ecotoxicity Evaluation of Environmental-friendly Organic Agro-materials Containing Pepper Extract, Cassia Oil, Lavender Oil for Control of Diamondbackmoth (배추좀나방 방제약제로서 후추 추출물, 카시아 오일, 라벤더 오일 함유 친환경유기농자재에 대한 급성 생태독성평가)

  • You, Are-Sun;Jeong, Mihye;Hong, Soon-Seong;Chang, Hee-Seop;Lee, Je Bong;Park, Kyung-Hun;Lee, Young Mook;Ihm, Yangbin
    • The Korean Journal of Pesticide Science
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    • v.17 no.4
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    • pp.343-349
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    • 2013
  • Environment-friendly agro-materials tend to be preferred to chemical insecticides recently. For this reason, many studies are conducted to develop environment-friendly insecticides containing natural materials. The purpose of this study was to assess ecotoxicity for pepper extract and cassia oil (11.5+46%, A), pepper extract and cassia oil (23+34%, B), and pepper extract and lavender oil (40+10%, C). They are expected to prevent from pests especially diamondback moth, and can be used for agro-materials. Their formulation was emusifiable concentration (EC). Target species used to assess acute toxicity were aquatic invertebrate (Daphina magna), fish (Cyprinus carpio), honeybee (Apis mellifera L.) and earthworm (Eisenia fetida). The $EC_{50}$ value of A, B, and C to aquatic invertebrate were 0.46, 1.9, 0.25 mg $L^{-1}$ respectively and these values were moderately toxic according to standard of USEPA. In case of acute toxicity test to fish, the $LC_{50}$ of A, B, and C were 1.9, 2.9, 3.8 mg $L^{-1}$ respectively. A was category II in acute toxicity of fish and not acceptable to evaluation criteria of environment-friendly agro-materials. B and C were category III and acceptable. Acute contact and oral toxicity test to honeybee were conducted and the $LD_{50}$ of A, B, and C were > 100 ${\mu}g$ a.i. $bee^{-1}$ in both of tests. It indicated they were low toxic to honeybee. In case of acute toxicity test to earthworm, $LC_{50}$ of A, B, and C were 695, 988, and 564 mg $kg^{-1}$. In conclusion, pepper extract+cassia oil 57% EC and pepper extract+lavender oil 50% EC were expected to be used for environment-friendly insecticide materials with low risk against ecosystem and contribute to developing environment-friendly agro-materials.

Effects of Light Intensity and Electrical Conductivity Level on Photosynthesis, Growth and Functional Material Contents of Lactuca indica L. 'Sunhyang' in Hydroponics (수경재배에서 광도와 양액 농도가 베이비 산채 왕고들빼기 '선향' 광합성과 생육 및 기능성 물질 함량에 미치는 영향)

  • Kim, Jae Kyung;Jang, Dong Cheol;Kang, Ho Min;Nam, Ki Jung;Lee, Mun Haeng;Na, Jong Kuk;Choi, Ki Young
    • Journal of Bio-Environment Control
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    • v.30 no.1
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    • pp.1-9
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    • 2021
  • This study was conducted to examine the changes of photosynthesis, growth, chlorophyll contents and functional material contents in light intensity and EC concentration of wild baby leaf vegetable, Indian lettuce (Lactuca indica L. cv. 'Sunhyang') in DFT hydroponics. The cultivation environment was 25±1℃ of temperature and 60±5% of relative humidity in growth system. At 14 days after sowing, combination effect of light intensity (Photosynthetic Photon Flux Density (PPFD 100, 250, 500 µmol·m-2·s-1) and EC level (EC 0.8, 1.4, 2.0 dS·m-1) of nutrient solution was determined at the baby leaf stage. The photosynthesis rate, stomatal conductance, transpiration rate and water use efficiency of Indian lettuce increased as the light intensity increased. The photosynthesis rate and water use efficiency were highest in PPFD 500-EC 1.4 and PPFD 500-EC 2.0 treatment. The chlorophyll content decreased as the light intensity increased, but chlorophyll a/b ratio increased. Leaf water content and specific leaf area decreased as light intensity increased and a negative correlation (p < 0.001) was recognized. Plant height was the longest in PPFD 100-EC 0.8 and leaf number, fresh weight and dry weight were the highest in PPFD 500-EC 2.0. Anthocyanin and total phenolic compounds were the highest in PPFD 500-EC 1.4 and 2.0 treatment, and antioxidant scavenging ability (DPPH) was high in PPFD 250 and 500 treatments. Considering the growth and functional material contents, the proper light intensity and EC level for hydroponic cultivation of Indian lettuce is PPFD 500-EC 2.0, and PPFD 100 and 250, which are low light conditions, EC 0.8 is suitable for growth.

Hepatoprotective Constituents of Saururus chinensis Roots Against Tacrine-induced Cytotoxicity in Human Liver-derived Hep G2 Cells (삼백초근의 타크린으로 유발한 간 세포독성 보호 성분)

  • Jeong, Gil-Saeng;Li, Bin;Lee, Dong-Sung;Kwon, Ji-Wung;Lee, Hye-Suk;Kwon, Tae-Oh;Kim, Youn-Chul
    • Korean Journal of Pharmacognosy
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    • v.38 no.2 s.149
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    • pp.176-180
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    • 2007
  • Five liglans, sauchinone (1), di-0-methyltetrahydrofuriguaiacin B (2), manassantin A (3), manassantin B (4) and saucerneol B (5), have been isolated from the MeOH extract of Saururus chinesis roots. The evaluation for protective effect of compounds 1-5 against tacrine-induced cytotoxicity in human liver-derived Hep G2 cells was conducted. Compounds 1,2, and 5 showed significant protective effects with the EC$_{50}$ values of74.2${\pm}$0.9, 111.3${\pm}$0.8,64.3${\pm}$0.8 ${\mu}$M, respectively. Silybin, one of the well-known hepatoprotective agents, used as a positive control, and also showed protective effect with an EC$_{50}$ value of 86.2${\pm}$0.5 ${\mu}$M.

Fabrecation and Characterization of $SrBi_2TaNbO_9$ Ferroelectric Thin Film Prepared by Sol-Gel Method (SOL-GEL법을 이용한 $SrBi_2TaNbO_9$ 강유전성 박막 제조 및 특성 평가)

  • 이진한;박상준;장건익
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.94-98
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    • 2000
  • Polycrystalline SBTN ferroelectric thin films were prepared by sol-gel method with various Nb mole ratios on Pt/ $SiO_2$/Si (100) substrates. The films were annealed at different temperatures and characterized in terms of phase and microstructure. Relatively a well saturated hysteresis pattern was obtained at x =0.2 in S $r_{0.8}$B $i_{2.3}$(T $a_{1-x}$ N $b_{x}$)$_2$ $O_{9+}$$\alpha$/ thin films. At an applied voltage of 5V, the dielectric constant ($\varepsilon$$_{r}$) and dissipation factor (tan $\delta$) of typical S $r_{0.8}$B $i_{2.3}$(T $a_{1-x}$ N $b_{x}$)$_2$ $O_{9+}$$\alpha$/ thin film (x=0.2) were about 236.2 and 0.034. Measured remanent polarization (2Pr) and coercive field (Ec) were 4.28C/c $m_2$, and 38.88kv/cm respectively. No fatigue was observed up to 6$\times$10$_{10}$ switching cycles at 5V and the normalized polarization reduced by a factor of only 4%.%. 4%.%. 4%.%.%.%.%.

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Desmutagenicity of Tea Extracts from Green Tea, Oolong Tea and Black Tea (녹차, 오룡차 및 홍차 추출물의 돌연변이원성 억제작용)

  • 김선봉;여생규;김인수;안철우;박영호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.1
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    • pp.160-168
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    • 1995
  • Desmutagenicities against 2-amino-1-methyl-6-phenylimidazo[4, 5-b] pyridine(PhIP) and 2-amino-3, 8-dimethylimidazo[4, 5-f]quinoxaline(MelQx) of tea extracts (steamed green tea, roasted green tea, oolong tea and black tea) were investigated. All the fractions obtained from tea extracts showed strong desmutagenic activity against PhIP and MeIQx toward S. typhimurium TA 98 in the presence of the S-9 mix. The crude catechin fraction exhibited the strongest desmutagenic activity. Among these tea extracts, black tea especially exhibited the strongest desmutagenic activity and the activity was 70.9~91.0% against PhIP and 92.2~98.8% against MelQx at a concentration(0.5~1.0mg/plate) for drinking. The activity of authentic catechins of (-)-EGC, (-)-EGCg, (-)-ECg and (-)-EC were 79.5%, 60.2%, 46.1% and 43.5% against PhIP, and were 52.3%, 11.6%, 8.2% and 22.1% against MelQx by addition of 1.0mg/plate, respectively. The desmutagenic activity was supposedly due to the (-)-EGCg, (-)-EGC and (-)-EC in tea polyphenols, and the browning materials. The desmutagenicity was stronger when mutagens were preincubated with S-9 mix after reaciton with black tea extracts than when preincubated with them after reaction with S-9 mix. The desmutagenicity of tea extracts was rather expressed by reacting directly with mutagens than by deactivating the activated forms of mutagens.

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A Study on Exposure Indices for Diesel Engine Exhaust in Forklift Operating Areas (지게차 사용 사업장에서 디젤엔진배출물질 노출지표에 관한 연구)

  • Kim, Sangil;Park, Ji Young;Lee, Kyeongmin;Kim, Seung Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.26 no.1
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    • pp.38-47
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    • 2016
  • Objectives: The objective of this study was to determine the exposure levels of forklift operators to diesel engine exhaust(DEE) using black carbon(BC), elemental carbon(EC), and nitrogen dioxide($NO_2$) as indicators. Methods: A total of eight forklift operators in six collection companies were assessed over a period of two months from July to September 2015. BC was measured using a real-time monitor and respirable EC samples were analyzed using the NIOSH method 5040. $NO_2$ samples were collected using a passive badge-type sampler. Results: The geometric mean of BC, EC and $NO_2$ were $3.1-19.1{\mu}g/m^3$, $2.1-23.8{\mu}g/m^3$, and 12.5-166.6 ppb at all companies. When forklifts were operating both outside and inside, BC concentrations increased 2.0-5.6 times. The highest increase was observed when forklifts were operating indoors. The increase in BC concentrations varied by company(company A: 2.0 times, B: 3.2 times, C: 5.6 times, D: 2.1 times, E: 5.1 times, F: 2.6 times). The geometric mean of BC, EC, and $NO_2$ for the forklift operators was $9.6{\mu}g/m^3$, $7.9{\mu}g/m^3$, and 48.9 ppb, respectively. The geometric mean of BC, EC, and $NO_2$ for manufacturing workers was $9.3{\mu}g/m^3$, $0.9{\mu}g/m^3$, and 85.2 ppb, respectively. The mean BC and EC exposure levels for the forklift operators were slightly higher than those for manufacturing workers, but $NO_2$ levels for manufacturing workers were higher than those for the forklift operators(p>0.05). Multiple regression analysis revealed that diesel exhaust emissions standard, forklift weight and forklift manufacturer were the most influential factors in determining worker exposure. Conclusions: In the DEE work environment, workers who perform tasks within the workplace as well as inside forklifts as operators are likely to be exposed to a lack of ventilation. Further study of forklift operators' exposure to DEE indicators should be conducted to include a wider range of occupational and environmental situations, such as collection procedures, seasonal situations, types of fuel used, and number of forklifts.

Fumonisin B1 Contamination of Cereals and Risk of Esophageal Cancer in a High Risk Area in Northeastern Iran

  • Alizadeh, Ali Mohammad;Roshandel, Gholamreza;Roudbarmohammadi, Shahla;Roudbary, Maryam;Sohanaki, Hamid;Ghiasian, Seyed Amir;Taherkhani, Amir;Semnani, Shahryar;Aghasi, Maryam
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2625-2628
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    • 2012
  • Introduction: Fumonisin B1 (FB1) is a toxic and carcinogenic mycotoxin produced in cereals due to fungal infection. This study was conducted to determine FB1 contamination of rice and corn samples and its relationship with the rate of esophageal cancer (EC) in a high risk area in northeastern Iran. Methods: In total, 66 rice and 66 corn samples were collected from 22 geographical subdivisions of Golestan province of Iran. The levels of FB1 were measured for each subdivision by thin layer and high pressure liquid chromatographies. The mean level of FB1 and the proportions of FB1 contaminated samples were compared between low and high EC-risk areas of the province. Results: The mean of FB1 levels in corn and rice samples were 223.64 and 21.59 ${\mu}g/g$, respectively. FB1 contamination was found in 50% and 40.9% of corn and rice samples, respectively. FB1 level was significantly higher in rice samples obtained from high EC-risk area (43.8 ${\mu}g/g$) than those obtained from low risk area (8.93 ${\mu}g/g$) (p-value=0.01). The proportion of FB1 contaminated rice samples was also significantly greater in high (75%) than low (21.4%) EC-risk areas (p-value=0.02). Conclusion: We found high levels of FB1 contamination in corn and rice samples from Golestan province of Iran, with a significant positive relationship between FB1 contamination in rice and the risk of EC. Therefore, fumonisin contamination in commonly used staple foods, especially rice, may be considered as a potential risk factor for EC in this high risk region.

Thelephoric acid and Kynapcin-9 in Mushroom Polyozellus multiflex Inhibit Prolyl Endopeptidase In Vitro

  • Kwak, Ju-Yeon;Rhee, In-Koo;Lee, Kyung-Bok;Hwang, Ji-Sook;Yoo, Ick-Dong;Song, Kyung-Sik
    • Journal of Microbiology and Biotechnology
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    • v.9 no.6
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    • pp.798-803
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    • 1999
  • Prolyl endopeptidase [PEP; EC 3.4.21.26], a serine protease which is known to cleave peptide bonds on the carboxy side of a proline residue, plays an important role in the degradation of proline-containing neuropeptides that have been suggested to participate in learning and memory processes. An abnormal increase in the level of PEP, which can lead to generation of $A{\beta}$, is also suggested to be involved in Alzheimer's type senile dementia. In the course of screening PEP inhibitors from Basidiomycetes, the mushroom Polyozellus multiplex exhibited a high inhibitory activity against PEP. Two active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification, using silica gel, Sephadex LH-20, and Lobar RP-18 chromatography. The chemical structures of these compounds were identified as thelephoric acid and 12-acety1-2,3,7,8-tetrahydroxy-[12H]-12-hydroxymethylbenzobis[I.2b,3.4b'] benzofuran-11-one (kynapcin-9) by spectral data including UV, IR, MS, HR-MS, $^1H-,{\;}^{13}C-$, and 2D-NMR. The $IC_{50}$ values of the thelephoric acid and kynapcin-9 were 0.157 ppm (446nM) and 0.087 ppm (212nM) and their inhibitor constants ($K_i$) were 0.73ppm ($2.09{\;}\mu\textrm{m}$) and 0.060 ppm (146 nM), respectively. Furthermore, they were non-competitive with a substrate in Dixon plots.

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