• Korean journal of applied entomology
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• v.33 no.1
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• pp.19-25
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• 1994

Electrophysiological recordings of antennal responses to common plant volatile chemicals in the rice brown planthopper, Niloparuota lugens (Homoptera: Delphasidae}, were examined. Volatile plant chemicals were generally credited with a major role In host plant location for food or egg laying by many insects feeding on plants as adults and/or as larvae. An mitial examination of extracellular responses has been conducted. Acton potentials recorded from the plaque organs were initially positive-going, biphaslc spikes and the background firing rate of the cells recorded ranged from 1 ~22 impulses/sec. A wide range of responses to changes in concentration of the test chemical was observed. The commonest response was a relatively small increase in exitation with increasing concentration beween 1 J.lg and 100).\g on the filter paper in syringe. Adtivity either peaked at 100 $\mug$ and remained virtually saturated at 1000 f19 or tended to decrease at the highest concentration.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.2
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• pp.57-66
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• 1988

Sandy dust phenomena was observed from April 19 to 23, 1988 in Seoul and suspended particulate was collected by Andersen air sampler during this period. The samples were analyzed for 16 components $(SO_n^{2-}, NO_3^-, Cl^-, PO_4^{3-}, NH_4^+, F^-, Al, Fe, K, Cu, Mn, Na, Pb, Mg, Ca, Cd)$. The conclusions are as follwes: 1. Total suspended particulate concentation during the period of sandy dust phenomena was 489 $\mug/m^3$ (ordinary times: 140-125 $mug/m^3$) 2. The water - soluble ion component concentration of suspended particulate during the period of sandy dust phenomena was few and the metal concentration of that was more than that of ordinary times. 3. The cumulative frequency distribution of suspended particulates in logarithmic diagram did not show similar to normal log distribution during the period of sandy dust phenomena. 4. $SO_4^{2-}, NO_3^-, Cl^-, and PO_4^{3-}$ was onsided to coarse particle, and $NH_4^+$ and F to fine particle in the size distribution of water - soluble ion components during the period of sandy dust phenomena. 5. Metal concentration was high and Al, Fe, Cu, Mn, Na, Mg, and Ca was onsided to coarse particle, and K, Pb, and Cd to fine particle in the size distribution of metal components. 6. During the period of sandy dust phenomena the quantity of respirable particle (< 1 $\mum$) was about 3 times and that of metal components were about 2 - 11 times than that of ordinary times. 7. The concentrations of $NO_3^-, Cl^-, NH_4^+$ at ordinary times were 1.1 - 4 time than that of the period of sandy dust phenomena.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3923-3926
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• 2013

• Journal of The Korean Radiological Technologist Association
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• v.29 no.1
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• pp.12-24
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• 2003

Purpose : The aim of this study was to investigate the variables affecting video display terminal (VDT) syndrom and prevent the harm of VDT syndrom Materials and Methods : A questionnarie study was performed with 170 radiotechnologists working at CT room

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.240.2-240.2
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• 2003

A strategy for synthesis of the furan-fused tetracyclic core of xestoquinone and halenaquinone was explored through a model study. Methyl 8-oxo-4-methyl-4-phenyl-2,7-nonadiynoate was prepared from hydratroponitrile and 3-butyn-1-ol as starting materials. The intramolecular cycloaddition of this intermediate as a key step will be involved.

• Journal of Environmental Health Sciences
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• v.9 no.1
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• pp.85-88
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• 1983

캄덴 카운티 청사에 있는 transformer에 화재가 난 후 건물내에 있는 60명의 혈야에서 PCB를 측정하였다. 화재가 발생한 건물내의 공기에서는 거의 검출되지 않았으나 transformer가 있는 방의 Swab Sample에서는 $52.6 \mug/cm^2$가 검출되었다. 건물을 재사용하기 전에 환기를 최대로 시킨후 다시 Swab Sample을 취했을때 12 Sample중 10주에서 PCB가 검출되지 않았다. 또한 혈야에서 PCB수준은 미검출에서 16ppb였으나 일반인에서도 69.2ppb까지 검출된것과 그밖에 17.6ppb까지 검출된 것으로 보아 화재후 PCB가 혈야중에서 증가했다는 증거는 없다고 본다. 이와 같이 혈청내에서 PCB가 증가하지 않은것은 화재후 즉시 청소와 환기를 실시한 결과로 본다.

• Journal of Life Science
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• v.13 no.5
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• pp.675-683
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• 2003

This study was conducted to investigate the physiological properties of various parts of skate body after fermentation by measuring compositional properties including pH and $NH_4^+$. Other functional properties, such as antibacterial activities, antioxidative activities and anticancer activities were measured. Effects of fermentation temperature (4, 10, $20^{\circ}C$) did not affect compositional properties of fermented skate. The pH of fermented skate extract at 4$^{\circ}C$ did not increase as much as that at 10 and $20^{\circ}C$, Particularly at $10^{\circ}C$, the pH increased rapidly after Day 1 and remained unchanged until another increase at Day 5. At 2$0^{\circ}C$, the pH increased rather rapidly at early stage of fermentation and reached 8.9 at Day 4. The pattern of $NH_4^+$ concentration of fermented skate extract was similar to that of pH. Particularly at $4^{\circ}C$ fermentation, $NH_4^+$ concentration was not affected by fermentation time. The concentration of $NH_4^+$. reached approximately $10.2\mug/mL$at $10^{\circ}C$ for Day 5 and $20^{\circ}C$ for Day 4-5, indicating the early stage of fermentation. According to physiological activities of hot water extracts of skate fillet and viscera as affected by fermentation time, antibacterial activity of 2% viscera extract concentration was 43.3% at Day 8, while there was no antibacterial activity from fillet extract. As for the antioxidative activity, fillet extract and viscera extract both at 2% concentration at Day 0 showed 61.2% and 54.4%, respectively. Anticancer activities were highest (52.7% for fillet extract and 58.3% for viscera extract) at $1,000 \mug/mL$ concentration at Day 8. Antibacterial activities and anticancer effects were relatively high as fermentation was progressed, while antioxidative activities were highest before fermentation started. As for the physiological activities of hot water extract from brain and cartilage, antibacterial activities were observed at 41.0% when 2% brain extract was added at 4 hours of incubation, while 35.8% with 2% cartilage extract at 14 hours of incubation. Antioxidative activities were not found in brain extract, but cartilage extract at 2% showed 25.0% of antioxidative activity, which was lower than fillet and viscera extract.

• Environmental Mutagens and Carcinogens
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• v.24 no.2
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• pp.99-107
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• 2004

The validation of many synthetic chemicals that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, the regulation and evaluation of the chemical hazard playa very important role to environment and human health. The clastogenicity of 11 synthetic chemicals was evaluated in Chinese hamster lung (CHL) fibroblast in vitro. Benzoyl chloride (CAS No. 98-88-4) induced chromosomal aberrations with statistical significance at the concentration of 31-123 $\mug/ml$ and 43 $\mug/ml$ in the absence and presence of S-9 metabolic activation system, respectively. 2-Propyn-l-o1 (CAS No. 107-19-7) and 2-Phenoxy ethanol (CAS No. 122-99-6) revealed clastogenicity only at the highest concentration in the presence of S-9 mixture. However, 1-naphthol (CAS No. 90-15-3) which is one of the most cytotoxic chemical among 11 chemicals tested revealed no clastogenicity both in the presence and absence of S-9 metabolic activation system. From the results of chromosomal aberration assay with 11 synthetic chemicals in CHL fibroblast in vitro, Benzoyl chloride (CAS No. 98-88-4), 2-Propyn-l-01 (CAS No. 107-19-7) and 2-Phenoxy ethanol (CAS No. 122-99-6) revealed positive clastogenic results in this study.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.455-460
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• 1998

In the course of screening for new antitumor substances, a novel cytotoxic agent inducing apoptotic cell death was isolated from the culture broth of marine bacterial strain SCRC A-20. Strain SCRC A-20 was separated from a mollusk and was chemotaxonomically identified as a Streptomyces sp. The cytotoxic substance was purified by organic solvent extraction followed by silica gel column chromatography and preparative TLC. HRFAB-MS determined its molecular formula to be $C_{30}H_{40}N_2O_5$ (MW 508). The 1D and 2D NMR spectral data demonstrated that the substance has a novel lactam structure of a 20-membered macrocycle coupled with a unique acyl tetramine and bicyclo［3.3.0］ octane, which includes three methyl groups, six olefinic protons, five carbonyl groups, a conjugated diene and a dienone. The substance, named aburatubolactam C, appeared to be cytotoxic for various continuously proliferating tumor cells of human and murine origins. The $IC_{50}$ values determined by MIT assay were in the range of 0.3 to $5.8\mug/ml$. When Jurkat T cells were treated with $3\mug/ml$. of aburatubolactam C, the apoptotic DNA fragmentation was detectable within 3 h, indicating that the cytotoxic effect of aburatubolactam C on tumor cells is attributable to the induced apoptosis.

• Journal of Korean Society for Atmospheric Environment
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• v.5 no.1
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• pp.68-78
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• 1989

The heavy metal of suspended particulates with human health has long been studied in environmental interest concerned. This study was intended to identify harmful heavy metals of the ambient air borne dusts which were related with the respirable sizes in the aerodynamics. Two sampling sites were selected comparatively; one was in the Shinchon area, which is the commercial district with heavy traffic and the other site was in the Bulgwang area which is residential area. The supended particulates were sampled by high volume air sample with 6 cascade impactor stages. The heavy metals in terms of As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn were determined by stomic absorption spectrometry or inductively coupled plasma emission spectrometry. The samples weretaken bimothly for seven consecutive days from May 1987 to March 1988. The annual average concentration of the respirable suspended dust of which diameter is less than 10$\mum$ was 152.59 $\mug/m^3$ of the Shinchon air samples; the respirable dust was equivalent to approximately 85% of the total suspended particulates. The annual average concentration of the respirable suspended dust of the Bulgwang air samples was 112.56 $\mug/m^3$; that was approximately 86% of the total suspended particulates. The concentration of heavy metals was investigated in relation to the particle size. The concentration of Cr, Fe, Mn and V were tended to be much more in the coarse particles than in the fine particles. Cd and Pb in the fine particles were more than in the coarse particles. In the partial correlation coefficients; in the Shinchon area, high correlations among Fe, Se and Mn were determined; it is assumed that those sources would be originated from coal, gasolineand diesel. In Bulgwang area, would be high correlation among Fe, Se, Hg and Mn considered to be originated from coal, Bunker-C and heavy oil as well. From the above results, the hazardous heavy merals in air should be measured and controlled in originally their sources.