• Environmental Mutagens and Carcinogens
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• v.20 no.1
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• pp.26-33
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• 2000

Genetic polymorphisms of metabolizing enzymes to chemical carcinogens have been recognized as a major important host factors in human cancers. To datermine the frequencies of genotypes of CYP1A1 and GSTM1 metabolizing enzymes in healthy controls and head and neck cancer patients in Korean and to identify the relative high risk genotypes of these metabolizing enzymes to head and neck cancer, we have analyzed 133 head and neck cancer patients and corresponding healthy controls matched in age and sex using polymerase chain reaction-restriction fragment length polymorphism (PCR-RELP). In analysis of CYP1A1, the Val/Val genotype of exon 7 polymorphism and m2/m2 genotype of Msp 1 polymorphism were associated with higher relative risks to head and neck cancers (Odds ratio : 2.34, 95% CI : 0.79-6.96 and 1.27, 95% CI : 0.59-2.73, respectively). In combined genotyping of CYP1A1 and GSTMI enzymes polymorphisms, the patients with Val/Val ad GSTM1(-), and m1/m21 and GSTM1(-) combined genotypes had higher relative risks than the patients with each base genotype of combined genotypes (Odds ratio : 4.57, 95% CI : 0.5-41.25 and 1.65, 95% CI L 0.73-3.77, respectively). These results sugget the combined genotyping of metabolizing enzymes could be useful for predicting individual genetic susceptibility and screening the high risk subpopulation to head and neck cancer in Korea.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.13-23
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• 2024

Vespa velutina nigrithorax du Buysson, 1905 is the invaded species in Korea since 2003. Since its importance as the honey bee pest, beekeepers use insecticides to kill the adult and immature hornets. However, its legality and effectiveness has not been confirmed. This study investigated the susceptibility of insecticides commonly used to control hornets by beekeepers in Korea. Eight insecticides were tested on adult worker and larvae by topical or oral treatment. Adults showed more than 70% mortalities from Clothianidin, Dinotefuran, and Carbosulfan treatment within 30 minutes. Bifenthrin and Cartap hydrochloride showed relatively low toxicity. The median lethal dose (LD₅₀) for Clothianidin, Dinotefuran, and Carbosulfan was 0.29, 0.65, and 2.21 ㎍/bee, respectively. In larval feeding test where 5^th instar larvae were fed 3 times every 24 hours, the mortality began after second treatments. After 3rd treatments (72 h), all insecticides showed mortality more than 70%. The LD₅₀ values of Clothianidin, Dinotefuran, and Carbosulfan to V. velutina were approximately 10 to 100 times higher than those to honey bee, Apis mellifera. This study provides the basic information of those chemical toxicities to Vespa hornet and honey bees.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.210-215
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• 2002

Four field experiments were carried out from 1998 to 1999 and from 1999 to 2000 growing seasons of potato to investigate the relationship between leafminers and Alternaria alternata. The experiments established differential susceptibility among potato varieties to alternaria leaf necrosis, relationship between leafminer infestation and the level of necrosis, use of insecticides to reduce leafminer and leaf necrosis damages, and use of polyester fleece to eliminate leafminer and eventually reduce leaf necrosis. Results of the study indicate that control of leafminer is of primary importance because this will automatically lead to control of the damage caused by A. alternata.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.106-111
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• 2001

Recently there were many studies not only to enhance drug delevery effect but to reduce side effect. Drug delivery system efficiency with decreasing side effect of drug dosage. It made possibility to use for a long term. Polymer drug was prepared by acid halide method with polymer in such of polyacylic acid and sulfacetamide. Its chemical properties were identified by means of IR, TGA. The antibacterial activities of polymer drug were studied by MICs and disk susceptivility test. The antibacterial activities by clean zone were increased in order of Staphyloccus aures

• Proceedings of the KOSOMBE Conference
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• v.1994 no.05
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• pp.9-15
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• 1994

In last few decades, medical imaging techniques have been developed startling progress. Especially in MRI (Magnetic Resonance Imaging), many imaging techniques such as chemical shift imaging, flow imaging, diffusion and perfusion imaging, fast imaging, susceptibility imaging and functional imaging have been studied and many of them were well known as useful diagnostic instruments. In this paper, recently developing techniques, i.e., NMR microscopy, fringe field imaging and functional imaging will be presented.

• Proceedings of the KSMRM Conference
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• 1999.04a
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• pp.34-42
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• 1999

의료영상에서 인공물(Artifacts) 이라 함은 영상이 얻어지는 신체부위와 아무런 관련이 없으나 얻어진 영상에는 마치 영상의 일부분으로 나타나는 모든 것을 가리킨다. 따라서 영상에서 이들 인공물들은 실제 조직의 해부학적인 구조를 나타내지 않으므로 영상 판독에 영향을 주어 잘못된 진단을 초래할 수도 있다. 그러나 MR 영상이 가능한 이래로 새로운 여러 종류의 MR 인공물들이 많이 발견 되었으나 다행스럽게도 거의 모든 MR 인공물들은 쉽게 설명이 가능하며, 따라서 이들 인공물들에 의한 진단 오류의 가능성은 매우 희박한 실정이다. 그러나 새로운 영상방법이나 혹은 새로운 펄스대열이 계속 고안됨에 따라 새로운 종류의 인 공물들이 생겨날 가능성은 항상 존재하고 있다. 지금까지 알려진 여러 MR 인공물들은 그 생겨난 원인에 따라 다음과 같이 크게 세 가지로 분류가 가능하다. I. Motion Artifacts 1. Voluntary motion 2. Involuntary motion 1) Bowel Peristalsis 2) Respiration 3) Cardiac and vessel pulsation 4) Swallowing 3. Fluid motion 1) Blood flow 2) Cerebrospinal fluid flow II. Reconstruction Artifacts 1. Aliasing 2. Partial volume averaging 3. Truncation (Ringing) 4. Central point III. Magnetic and RF Field Related Artifacts 1. Chemical shift 1) First kind 2) Second kind 2. Susceptibility 1) Dental 2) Metal 3. Magic angle 4. Zipper 5. Bad data point 6. RF field inhomogeneity 7. Magnetic field inhomogeneity 8. Eddy current 9. slice overlapping 10. Zebra 11. RF overflow

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1174-1179
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• 2003

Cast austenitic stainless steel is used for several components, such as primary coolant piping, elbow, pump casing and valve bodies in light water reactors. These components are subject to thermal aging at the reactor operating temperature. Thermal aging results in spinodal decomposition of the delta-ferrite leading to increased strength and decreased toughness. This study shows that ferrite content can be predicted by use of the artificial neural network. The neural network has trained learning data of chemical components and ferrite contents using backpropagation learning process. The predicted results of the ferrite content using trained neural network are in good agreement with experimental ones.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.131-132
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• 2011

This study analyzes the yearly-best delivered size range of truck mixer based on the specified mix, Water to Binder Ratio, aggregate proportion and unit amount with statistical method targeting on Kyeongi and Kyeongsang province and compares with the similar materials of Japan to propose as a basic standard for the quality control of mixer truck. As a result, in case of the Water to Binder Ratio of these areas, it is higher than Japan's due to the excessive safety rate reflecting the changes of differential value impact and unit amount, and the unit amount's standard deviation is very large by reflecting the changes of the amount used and chemical admixture susceptibility. In case of aggregate proportion, the frequency rate is about 50%, which is very similar value with Japan's one.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.4
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• pp.460-466
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• 2004

Cast austenitic stainless steel is used for several components, such as primary coolant piping, elbow, pump casing and valve bodies in light water reactors. These components are subject to thermal aging at the reactor operating temperature. Thermal aging results in spinodal decomposition of the delta-ferrite leading to increased strength and decreased toughness. This study shows that ferrite content can be predicted by use of the artificial neural network. The neural network has trained teaming data of chemical components and ferrite contents using backpropagation learning process. The predicted results of the ferrite content using trained neural network are in good agreement with experimental ones.

• Research in Plant Disease
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• v.17 no.1
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• pp.13-18
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• 2011

This study was conducted to establish the efficient screening method for resistant cabbage to Fusarium wilt caused by Fusarium oxysporum f. sp. conglutinans. The resistance degrees of nine commercial cabbage cultivars to the disease were evaluated. Among them, five cultivars (YR-honam, Ogane, Greenhot, Redmat, and Ccoccoma) showing different resistance to the fungus were selected. Then development of Fusarium wilt of the cultivars according to several conditions including root wounding, dipping period of roots in spore suspension, inoculum concentration, and incubation temperature to develop the disease was investigated. Highly resistant cultivars such as 'YR-honam' and 'Ogane' hardly showed change of resistance to the disease by root wounding, dipping period, and inoculum concentration, while disease severity of Fusarium wilt on the cultivars was changed with incubation temperatures ($20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$). When the cabbage cultivars were incubated at $25^{\circ}C$, they represented the most difference of resistance and susceptibility to Fusarium wilt. From above results, we suggest that an efficient screening method for resistant cabbage to F. oxysporum f. sp. conglutinans is to dip the non-cut roots of 14-day-old seedlings in spore suspension of $1{\times}10^7$ conidia/ml for 0.5 hr and to transplant the seedlings to plastic pots with a fertilized soil, and then to cultivate the plants in a growth chamber at $25^{\circ}C$ for 3 weeks to develop Fusarium wilt.