• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.88-96
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• 2005

Paraquat-resistant biotype of Conyza canadensis (L.) Cronq. was determined by chlorophyll loss and random amplified polymorphic DNA (RAPD) analysis and the resistant mechanism was investigated with respect to absorption, translocation, and binding constant. RAPD analysis for paraquat resistant (R) and susceptible (S) biotypes found in a pear orchard revealed that the biotypes possessed remote genetic relationship. Chlorophyll loss, as an indication of paraquat toxicity, of S biotype was 7.8-fold greater than that of R biotype. There were no differences in contents of epicuticular wax and cuticle and amounts of [14C]paraquat penetrating the cuticle between the two biotypes. Little translocation of the herbicide out of the treated leaf was observed in either biotype. Binding constants of paraquat to the cell wall and thylakoid membrane were 7.4-fold and 16.9-fold, respectively, higher in R biotype than in S biotype. The results suggest that the resistance mechanism of C. canadensis biotype is due partly to high binding affinity of paraquat to the cell wall and thylakoid membrane.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.193-197
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• 1977

Seeds of pea cultivars susceptible to damping-off caused by Pythium ultimum produced sugars intheir exudates in half the time required for resistant cultivars. Also, the amount of reducing sugars was much greater in seed exudates of susceptible than resistant cultivars. Raffinose, melibiose, sucrose, glucose, and fructose (but not maltose, xylose or ribose) were identified in both resistant and susceptible cultivars; however, more glucose and sucrose were detected in seeds from susceptible than from resistant cultivars. Pythium ultimum grew more profusely around seeds from, and in exudates of, susceptible than resistant cultivars.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.298-304
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• 2002

The inheritance of resistance to gall mite(Eriophys macrodonis) in boxthorn cultivars was studied with plants infected in open field. Segregation of the F$_1$ generation from crosses between resistant cultivars(Japan 1 and China 1) and susceptible line(CL42-56) hits a 3 resistant : 1 susceptible ratio, and the segregation ratio was 15 : 1 in cross between Japan 1 and China 1. It is concluded that gall mite resistance seemed to be controlled by two duplicate genes(El and E2), such that E1e1E2e2 symbolize the genotypes of China 1 and Japan 1. However, F, generation from Chungyanggugiza and CL42-56 cross did not showed clear segregation pattern but continuous variation was observed against gall mite resistance when resistance was determined on the basis of the percentage of galled leaves. Results indicated that the inheritance of resistance in Chungyanggugiza may be polygenic and complex. Also, Japan 1 and China 1 has a strong potential as a source of gall mite resistance, and Chungyanggugiza showing less resistance still has a valuable source.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.166-173
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• 1997

1993년부터 1995년까지 약 3개년 동안 우리 나라에서 사육하고 있는 가축의 유병율을 조사한 결과, 닭 16,200수 중에서 54수(0.3%)가 괴사성 장염에 이환 되었으며 새끼돼지 620두 중에서 9두(13.8%)가 장독혈증에 이환 되었다. C. perfringens의 분리율을 조사한 결과, 괴사성 장염에 이환 되어있는 닭 54수 중 7수(13.0%)에서 본균이 분리되었으며 장독혈증에 이환 되어있는 새끼돼지 66두 중 14두(21.2%)에서 본균이 분리되었고 장독혈증에 이환 되어있는 소 9두 중 3두(33.3%)에서 본균이 분리되었다. Acriflavine을 이용하여 C. perfringens의 S-R변이를 조사한 결과, S-R변이는 mercuric chloride, nicotine, caffeine, cysteine, glucose 등의 순으로 나타났는데, 이중 mercuric chloride가 가장 감수성이 높았다. C. perfringens의 항균요법제에 대한 감수성은 cepalothin, penicillin, erythromycin, amikacin 등이 높은 감수성을 나타내었는데, S-R변이 후에는 감수성이 일반적으로 저하되는 경향이었다. 중화시험법을 이용하여 C. perfringens의 독소형을 분류한 결과, cd 24균주 중 22균주(91.7%)는 A형이었으며 2균주(8.3%)는 C형이었다.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.319-328
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• 1995

This study was carried out to investigate the resistance mechanism by three different kinds of procymidone-resistant and susceptible isolates of Botrytis cinerea which had been collected from green houses. The average resistance level of the resistant strains was 1,000 times higher than that of susceptible ones. Also, it was revealed that the resistance was not originated from components excreted by Botrytis cinerea, based on the result obtained from the treatment with piperonyl butoxide and triphenyl phosphate as an inhibitor of monooxygenase and esterase, respectively. The total lipod content of resistant strains was 1.3 times higher than that of susceptible ones, among fatty acids, palmitic acid, stearic acid, and linoleic and being 3.0, 2.5, and 2.0 times higher, respectinely. Also slight differences in sterol contents and components were observed. The crude chitin content was slightly higher in susceptible strains but contents of N-acetyl glucosamine, a hydrolysate of chitin, were about 2 times higher in resistant ones.

• Biomedical Science Letters
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• v.5 no.2
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• pp.213-217
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• 1999

In order to control resistant strains and to properly select the antimicrobial agents, it is of quite importance to know current trends of bacterial species and changing patterns of antimicrobial resistance rates. The authors studied the results of 542 Gram-positive strains among 1,689 strains isolated at Chung-buk National University Hospital in 1996. The frequently isolated Gram-positive microorganisms were Staphylococcus aureus, Streptococcus pneumoniae, Staphylococcus epidermidis and Enterococcus faecalis in descending order. S. aureus showed high resistance to penicillin, gentamicin, and susceptibility to teicoplanin and vancomycin. Coagulase negative Staphylococcus was highly resistant to all of the antibiotics used in this experiment except teicoplanin and vancomycin. Enterococcus were highly resistant to vancomycin, penicillin and tetracycline. MIC of Gram-positive oaganisms was appeared to be zig-zag pattern.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.259-264
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• 1993

The experiment was carried out to investigate Insecticide susceptibility of the spiraea aphid (Aphis citricola) in apple orchards In Korea, using dipping method. Although insecticIde susceptibility vaned with local and seasonal populations, the susceptibility to demeLon S-rnethyl and phosphamidons was different from that Lo the other insecticides. The LCso values were 10 ppm for deltamethrin and chloropyrifos, 103 ~ 629 ppm for demeton S-methy1, acephate, phosphamidon, monocrotophos and vamldothion, 12,200 ppm for EPN, and 1,745 ppm for pirimicarb. 'When Insecticide susceptibility was compared between the S-clone selected from a population on the host plant spiraea and the R-clone selected from a population on the apple tree, the resistance ratio as expressed by RIS ratio of $LC_{50}$ was 78 for phosphamidon and 546 for pirimicarb. Esterase zymogram determined by the agar gel electrophoresIs revealed a significant difference between the clones. The activity of the E2, E5, E6 and E7 of the R-clone was higher than that of the S-clone, It is suggesLed that the Increased esterase activity may be involved in the mechanism of insecticide resistance in the spiraea aphid, although the involvement of other factor(s) may not be ruled out.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.1-7
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• 1988

Out of 24 isolates of Alternaria collected from pear leaves, only 7 isolates from cv. Nijiseiki leaves were specifically pathogenic to susceptible pear cultivar(Nijiseiki). Other isolates from cv. Chojuro, Oksankichi and Sinko did not show any pathogenicity to pear leaves. Pathogenic isolates of Alternaria kikuchiana produced host-specific toxin (AK-toxin) in liquid culture which caused veinal necrosis only on susceptible pear leaves, while nonpathogenic isolates did not produce this toxin. Varietal susceptibility among pear cultivars to the pathogen was investigated by evaluating HST (AK-toxin) sensitivity of pear leaves, as a substitute for spore inoculation. AK-toxin which the fungus produces was toxic to pear cultivars susceptible to the pathogen such as Isipsegi and Sinsu, but was harmless to resistant pear cultivars such as Chojuro, Oksankichi, Niitaka etc. Changes in disease susceptibility and toxin sensitivity of pear leaves with aging was investigated. Disease susceptibility and toxin sensitivity in cv. Sinsu leaves appeared to vary with leaf aging; the young leaves were visibly susceptible, but older leaves (more than 2 week old leaves) became resistant.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.191-200
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• 2013

This study set out to explore the human rights sensitivity of undergraduates who were in the social welfare classes with regards to socio-demographic factors, education experiences in human rights. 251 students' data were collected and analyzed with frequency, ANOVA. Analysis revealed that students' human rights sensitivity level was 2.70(moderate) and the respondents showed high level of sensitivity in work rights of emigration workers and education rights of handicapped children. Among demographic variables, human rights sensitivity was significantly different from major and experiences of attending a social welfare ethics. The students who majored social welfare and who had attended a social welfare ethics showed high human rights sensitivity. There were differences in human rights sensitivity level according to each episode. These findings highlight that in the education of social worker as a human rights professionals it would be necessary to respect students' rights in the classes and to provide student customized human rights education. It was suggested that learning human rights dilemma cases and self reflection processes in classes would be necessary to effective human rights education.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.15-20
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• 1970

An investigation was carried out to know the relationship between resistance of rice varieties to blast disease and the chemical components, especially total nitrogen and total sugars, in the rice plants. The results sic summarized as follow: 1) The nitrogen contents in the resistant variety were less than those of susceptible one, and sugar contents were reversed. Accordingly, the C/N ratio in the resistant variety was higher than that obtained by susceptible one. 2) The free amino acids contents, especially, Glutamine, Valine, Leusine and Iso-leusine, in the resistant varieties were more than those of the susceptible varieties. 3) The starch synthetic activity of rice leaves in the resistant varieties was higher than that of susceptible one in fructose and glucose solutions, but it was reversed in sucrose solution. 4) When more nitrogen was dressed, the total nitrogen content of rice leaves was increased than the ordinary dressing. The rate of increase in nitrogen content in resistant variety was lower than those of the susceptible. The total sugar content of rice plants dressed more nitrogen was decreased at early tillering stage, but increased at maximum tillering stage. It seemed that the rate of increase of total sugar in the resistant variety was higher than those of the susceptible.