• Korean journal of applied entomology
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• v.60 no.2
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• pp.201-202
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• 2021

We confirmed the convenient bioassay method for the black cutworm, Agrotis ipsilon in semi-field conditions. And we surveyed the susceptibility to commercial pesticides of A. ipsilon, which feeds Chinese cabbage through this bioassay process. As a result of the test, six soil mixing insecticides and eight soil drenching insecticides showed more than 90% insecticidal activity.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.66.4-67
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• 2020

Gyeonggi science high school for the gifted (GSHS) installed 60cm telescope, which is waiting for student observers. It is essential to understand the characteristics of the photometric system, consisting of telescope, filter, and CCD, to get reliable data. CCD images of SA98 Landolt standard field and M67 were obtained on 19th March 2020. The images of each field were combined by filters, i.e., we ignored the monochromatic atmospheric extinction since the photometric objects themselves are standard stars. 24 standard stars in SA98 field and 12 standard stars in M67 were used to derive the tentative transformation equation between our bv photometric system and Johnson BV photometric system. In this poster, we present the preliminary standardization result for Johnson BV photometric system in GSHS 60cm telescope. The reproductivity is discussed by comparing color coefficients of two fields. We plan to extend this process to Johnsons-Cousins BVRI photometric system and narrow-band filters for flux calibration.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.284-291
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• 2014

We surveyed the distribution of exotic weeds in the 350 upland crop fields of Gyeonggi-do. The exotic weeds were summarized as 78 taxa including 19 families, 52 genera, 74 species and 4 varieties. Among the total exotic weeds, the summer annuals were 48.7%, the winter annuals 28.2%, and the perennials 23.1%. Compositae was dominant family (32%), followed by Gramineae (8%), Polygonaceae (8%) and Malvaceae (7%). Dominant exotic weeds in northern Gyeonggi-do were Amaranthus lividus, Ambrosia trifida, Chenopodium album, Bidens frondosa and Erigeron Canadensis, and in southern Gyeonggi-do were Chenopodium album, Erigeron Canadensis, Erigeron annuus, Taraxacum officinale and Galinsoga ciliate. The most dominant exotic weeds in the Gyeonggi-do were Chenopodium album, followed by Amaranthus blitum, Erigeron canadensis. Canonical correspondence analysis for investigation of correlation between exotic weeds occurred in northern and southern Gyeonggi-do showed that the exotic weeds in northern Gyeonggi-do were more diverse then in southern Gyeonggi-do. This information could be useful for establishment of exotic weed control methods in Gyeonggi-do.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.311-316
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• 2007

Trans fatty acid components separated and quantified using a SP-2560 capillary column in a gas chromatograph (GC) with flame ionization detector (FID). Trans fatty acid and total fatty acid contents were measured in 21 corn oils. Ranges of values for trans fatty acid (tFAs) contents of total fat (as g/100g fatty acids) were com oils $0.65{\pm}0.31$. Corn oils were heated at $175{\pm}5^{\circ}C$ for 5mins $(0{\sim}15\;times)$. The contents of tFAs (g/100) were increased from 0.292 (0 time) to 2.585 (15 times) in com oil. When frying oils (15 times) were incubated at $20{\pm}5^{\circ}C$ for 150 days, the contents of tFAs (g/100g) were increased from 2.585 to 3.683 in com oil. The amounts of tFAs (g) per serving size of frying oils (15 times) were increased from 0.01 to 0.18 in corn oil. The levels of the 18:1 trans isomers increased significantly the time of reusing of com oil.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.257-267
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• 2007

The possibility of rapid non-destructive qualitative and quantitative analysis of vegetable oils such as perilla, com, soybean and rapaseed oils in sesame oils was evaluated. A calibration equation calculated by MPLS(Modified Partial Least Squares) regression technique was developed and coefficients of determination for perilla oil, com oil, soybean oil and rapaseed oil contents were 0.9992, 0.9694, 0.9795 and 0.9790 respectively. According to the data obtained from validation study, $R^2$ of contents of perilla, com, soybean, rapaseed oils were 0.997, 0.848, 0.957 and 0.968, and SEP of content of them 0.747, 5.069, 3.063 and 3.000 by MPLS respectively. The results indicate that the NIRS procedure can potentially be used as a non-destructive analysis method for the rapid and simple measurement of sesame oil mixed with other vegetable oils. The detection limits of the NIRS for perilla oil, com oil, soybean oil and rapaseed oil were presumed as 2%, $15{\sim}20%,\;15{\sim}20%$ and 10%, respectively.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.145-150
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• 2012

This study was carried out to investigate the degradation of six residual pesticides (${\alpha}$- and ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole, EPN) in red pepper powder after ultraviolet (UV) irradiation. The residual ratio of pesticides after 365 nm irradiation which distance is 20 cm and irradiation time is 5 minutes were 73.4, 69.6, 60.8, 92.7, 73.8 and 90.5% in ${\alpha}$-Endosulfan, ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole and EPN, respectively. The residual ratio of pesticides after 254 nm irradiation which distance is 5 cm and irradiation time is 36 hours were 74.6, 64.5, 71.1, 79.1, 79.4 and 64.7% in ${\alpha}$-Endosulfan, ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole and EPN, respectively.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.85-97
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• 2012

The monitoring of pesticide residues was performed on 33 fruit commodities collected in Gyeonggi-do, Korea from 2006 to 2010. Pesticide residues were detected in 431 samples (16.8%) of total 2,558 samples and violated in 12 samples (0.5%). Annual detection rate showed 6.9%~19.4% with the rate of violation of 0.3%~0.9%. Twenty three samples (69.7%) of 33 commodities were detected and 4 samples (12.1%) were violated. Eight pesticides (EPN, dicofol, carbaryl, procymidone, methidathion, prothiofos, fenitrothion and phenthoate) were violated and 62 pesticides were detected. Chloropyrifos was detected most frequently. The rate of detection and violation of citrus fruits in fruits showed the highest level. Organophosphorus pesticides (35%) and insecticide (57%) were detected most frequently. The hazard index (%ADI) of chronic dietary risk assessment by deterministic approach showed that the lower limit value and upper limit value for the whole population were 0.0000~0.7526 and 0.0000~1.3237 respectively. For the only consumer group, the lower limit value and upper limit value were 0.0006~9.7801 and 0.0058~15.9258 respectively. Therefore the hazard index for the whole population and the only consumer group were evaluated as a safe level.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.175-179
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• 2012

Adenoviruses are an important cause of respiratory tract infections, particularly in infants, young children, and immuno-compromised patients. In this study, we investigated the characteristics of adenoviruses isolated from outpatients with acute respiratory illness in Gyeonggi province of South Korea during 2009-2011. Adenoviruses were detected in 102 of 1,622 (6.3%) specimens by using PCR or real-time PCR with viral specific primers. 76 isolates were obtained from 102 specimens using the A549 cells. Serotypic distributions of isolated adenovirus were analyzed by sequencing of hexon gene. Six different serotypes were identified, which included adenovirus serotypes 1-6. Adenovirus 3 (n=40, 52.6%) was the predominant serotype. The predominant types of adenovirus every year were serotypes 1 and 3 in 2009, serotype 3 in 2010, and serotype 5 in 2011, respectively. Adenoviruses 1, 2, 4, 5, and 6 were isolated sporadically throughout the study period. Adenovirus 3 was present both during outbreaks and in sporadic cases. These results indicate that adenovirus 3 played major causative agent of adenovirus outbreaks in Gyeonggi province of South Korea during 2009-2011. Continuous surveillance for specific serotypes of adenovirus that can cause outbreaks is important.

• Journal of Korean Society on Water Environment
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• v.31 no.4
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• pp.377-386
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• 2015

The purpose of this research was to suggest the water quality improvement in streams by evaluating the distribution characteristics of organics and ammonia nitrogen discharged by pollution sources from human living. The public sewage treatment plants'(PSTPs) effluents and the waters from streams in Gyeonggi-do were sampled and analyzed. Nitrogenous oxygen demand (NOD) was measured for the stream waters as well as the PSTPs effluents, and the correlations of NOD and $NH_3$-N, $NH_3$-N and water temperature in the PSTPs effluents were confirmed. In the case of the stream waters, the ratios of NOD to BOD and $NH_3$-N increased in the downstream sites after discharging the PSTPs effluents. As a result of statistical analysis of $NH_3$-N concentrations for the national water quality monitoring streams in Gyeonggi-do, $NH_3$-N showed the non-normal distribution which were biased to the left, but showed the considerable level because of higher coefficient of variation. Therefore, it is required to establish the water quality standard for the $NH_3$-N as a new parameter for judging the quality of the streams. In addition, inducing complete nitrification and introducing a logical standard setting system are needed to improve the water quality of streams by identifying distribution of the nitrogen components from PSTPs effluents.

• Korean Journal of Microbiology
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• v.53 no.1
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• pp.1-8
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• 2017

Measles virus is a highly contagious, exanthematic virus, preventable by the use of an effective live-attenuated vaccine. However, measles virus remains endemic in many area of the world causing nearly 200,000 deaths per year and still a major cause of child mortality, mostly in developing countries. In March 2014, Republic of Korea was certified as a 'national measles elimination' by the WHO as a result of a high-quality case-based surveillance system and population immunity, which was achieved by a high vaccination rate (>95.0% since 1996). But, since the beginning of 2014, the Gyeonggi province has experienced a resurgence of measles cases. In this study, we investigated the characteristics of measles viruses isolated from confirmed measles in Gyeonggi province during January 1, 2014 ~ July 31, 2014, 60 isolates were obtained from 72 confirmed measles specimens. Genotypic distributions and genetic diversities of isolated measles virus were analyzed by sequencing of nucleoprotein (N) gene. 58 (96.7%) imported cases were identified. The predominant genotype was B3, which reflects the circulating measles virus in adjacent countries. The sequences of nucleoprotein (N) gene of isolated MeV were showed that the strains characterized showed the highest degree of identity (99%) with the Philippine related strains in 2013-2014. Therefore, infected traveler returning from the Philippines transmitted secondary infection in Korea.