• Korean journal of applied entomology
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• v.40 no.3
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• pp.265-271
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• 2001

Resistance mechanisms in the green peach aphid (Myzus persicae) resistant to imidacloprid were investigated. Imidacloprid residues on the aphid integuments decreased slowly as time passed with no significant difference between the susceptible and resistant strains. Residue in the aphid body increased in both strains with time elapse, and was slightly more in the susceptible strain. A higher metabolic rate of imidacloprid in the resistant strain can be expected by the fact that more amount of imidacloprid were excreted in the resistant strain than in the susceptible one. The activity of AChE was higher 1.4 times in the resistant strain than in the susceptible one, and imidacloprid did not inhibit AChE at all in both strains. Piperonyl butoxide (PBO) and iprobenfos (IBP) synergized imidacloprid activity. The mixtures of imidacloprid and PBO (1 : 1 and 1 : 5) caused 69.4- and 250-fold increase of imidacloprid toxicity against the aphid. Insecticide toxicity of the mixtures of IBP and imidacloprid (1 : 1 and 1 : 5) was also increased 227 and 80.6 times. Esterase activity when $\alpha$-naphtyl butyrate and $\beta$-naphtyl acetate were used as substrates was higher in the resistance strain than in the susceptible one. This means that P450 monooxygenase and esterase are responsible for the resistance to imidacloprid in this aphid strain.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.301-310
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• 2009

For the comparing of mortality of the resistance and susceptible population of Myzus persicae, etofenprox was treated in the recommended concentration of 200ppm. Mortalities of resistance population were 16.7 and 36.7%, and susceptible population were 86.7 and 86.7% after 24 and 48 hours treatment, respectively. For the detect of cross resistance to other pyrethroids, 6 pyrethroids were examined. Mortalities of susceptible and resistance populations were 90 and 31% to deltamethrin, 92 and 23% to lambda cyhalothrin, 81 and 14% to cypermethrin, 70 and 20% to $\alpha$-cypermethrin, 29 and 28% to fenpropathrin, 84 and 29% to fenvalerate, respectively. It was showed that resistance populations were generally resistive to other pyrethroids. On the other hands, for recognized ecological characteristic of M. persicae susceptible and resistance populations life table was tested on the pepper leaves in the petri dish and on the plant in the pot. This results were showed that intrinsic rate of increase ($r_m$), net reproduction number ($R_0$) and generation time in day ($T_c$) were significantly different between two population in both tested. However, life span and reproduction period were slightly different between them. Otherwise, feeding behaviors were tested using EPG technique with non- and treated etofenprox. First potential drop time of susceptible and resistance population was 73.5 and 257.9 sec with non-treated and 93.3 and 1076.2 sec after treated, respectively. Electrical probing signals were 8.2 and 48.8 times with susceptible and resistance individuals after treated etofenprox, respectively. It was supposed that the resistance is more probings than susceptible population. After treated, total feeding time have more 6,728.9 sec on resistance than 965.5 sec on susceptible population. So, total non penetration time of susceptible population was 3,000 sec longer than resistance population.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.321-326
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• 2001

Contribution of Wolbachia infection to fitness of a species (developmental time, adult life span, fecundity and ovipositional period) was measured in the susceptible and dicofol-resistant strains of two spotted spider mite, Tetranychus urticae Koch, on miniature roses. Based on ftsZPCR assay, Wolbachia infection was confirmed only in the susceptible strain. The susceptible strain had significantly higher fecundity (eggs/female) and shorter developmental times than the resistant strain. Longer adult life span and ovipositional period were observed in the susceptible strain. Fitness differences were appeared to influence dicofol resistance development. Similar measurements were performed with progeny from two reciprocal $F_1$crosses. Similar to other examples of cytoplasmic incompatibility induced by Wolbachia, subsequent cross between uninfected female and infected male spider mites were different from the other combination: a high egg mortality and a male-biased sex ratio. When the intrinsic rate of natural increase was calculated, the cross between uninfected female and infected male spider mites had a significantly lower rate($0.09\pm$0.01) than did the other combination ($0.20\pm$0.01). These results suggest that the dynamic and evolution of the fitness are closely associated with dicofol resistance and Wolbachia infection in the two spotted spider mites.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.133-136
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• 1975

Influence of susceptible and resistant soybean varieties to the development of the soybean cyst nematode(Heterodera glycines) was examined. It does not seem likly that there are any differences between varieties in attracting the Second Stage larvae of the nematode. In susceptible varieties, there were large populations and three generations during a ten·week examination period, while the resistant varieties maintained very low populations and had only two generations.

• Journal of Gastric Cancer
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• v.7 no.3
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• pp.160-166
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• 2007

Purpose: Recently, chemosensitivity tests have become widely used for the selection of effective drugs in gastric cancer patients. In this study, a chemosensitivity test was performed to select agents to increase the effectiveness of adjuvant chemotherapy. Materials and Methods: Chemosensitivity testing was performed in 81 gastric cancer patients that received a gastrectomy at the Yeungnam University Hospital. An ATP (adenosine triphosphate) based chemotherapy response assay was used. Clinicopatholgical factors such as sex, age, expression of tumor markers (CEA and CA19-9 levels), location of the tumor, morphology of advanced cancer, histological type, cell differentiation, depth of invasion, Lauren classification, Ming classification, lymphatic invasion, vascular invasion, neural invasion, lymph node metastasis and TNM stage were used to correlate the chemosensitivity and clinicopathological factors. Results: The most effective antitumor agents in gastric cancer patients were (in order of effectiveness) 5-FU, Epirubicin, lrinotecan and Oxaliplatin in our series. The chemosensitivity test showed a significant difference in susceptibility according to clinicopathological factors. Conclusion: Further studies on multidrug therapy are needed to evaluate synergistic effects of drugs. Therefore, for effective chemotherapy, it is more efficacious to select a chemosensitive drug than continue to use the same drug regimen.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.45-54
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• 1999

In epistatic grouping of uvs genes in A. nidulans based on the sensitivities to 4-NQO, the same epistatic grouping was obtained as those for UV and MMS-sensitivities. Based on the MMS-sensitivities, uvsA demonstrated synergistic interactions to uvsF and uvsH, the UvsF group genes, but exhibited epistatic interactions to uvsB and uvsC. The same epistatic grouping was also seen for uvsI when UV was irradiated after 4h germination of conidia, showing synergistic interactions to uvsH, uvsC, and uvsB. However, epistatic interactions were observed with uvsF, which were different from those obtained in quiescent conidia by UV. Intergenic and intragenic recombination frequencies were normal in uvsI compared with wild type.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.380-390
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• 2005

This study was carried out for looking into the status of susceptibility of vinyl house insect pests to insecticides. The Thrips (Thrips palmi and Frankliniela occidentalis), Mites (Tetranychus urticae), Aphids (Aphis gossypii) and Whitefly (Trialeurodes vaporariorum) were captured at various areas where the host crop was being cultivated and the susceptibility level of each pest insect was investigated. The susceptibility of each pest insect varied by insect species and areas where they were caught. The tested insecticides showed good control effect to palm thrips in 2000, but in 2003 showed decrease of effect to them. Western flower thrips showed low susceptibility to neonicotinoids, imidacloprid and thiamethoxam, but high to chlorfenapyr, spinosad, emamectinbenzoate and fipronil. Antibiotic insecticides, abamectin and milbemectin, and chlorfenapyr were very effective on mite control and dicofol still had good effectiveness to it despite of long year use. No aphid species showed resistance to pyrethroid and carbamate insecticides. Relatively new insecticides such as imidacloprid, spinosad, pymetrozine were effective to whitefly, but not were organophosphates, carbamates and pyrethroids.

• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.455-458
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• 1996

난 탄저병균의 배양적 특성과 탄저병의 발생 특성을 조사하였다. 자연 발병한 양란과 호접란의 잎에는 초기에 암갈색 또는 검은색의 둥글고 작은 반점이 형성되어 점차 진전되면서 검게타고 병이 진전됨에 따라 잎전체가 고사하고 심할 경우 줄기와 식물체 전체가 고사하였다. 탄저병에 감염된 양란과 호접란의 병환부로부터 분리된 Colletotrichum gloeosporioides는 상처접종에 의해서만 각각 양란과 호접란 병원성을 나타내었고, 덴파레 및 춘란에 대해서도 모두 병원성을 나타내었다. 양란은 상위엽일수록 탄저병균에 대해 감수성을 나타내었으며, 호접란이 탄저병균에 대해 감수성을 나타낸 반면에 춘란이 가장 저항성을 나타내었으며 양란과 덴파레는 중도 반응을 보였다. 탄저병균의 균사생장과 분생포자형성 적온은 각각 $25^{\circ}C$였으며, 베노밀 수화제와 비타놀 수화제에 대하여 감수성을 나타내었다.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.394-400
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• 2017

This study investigated whether culture filtrates produced by Xylella fastidiosa can be used to determine the varietal susceptibility to Pierce's disease in grapevines (Vitis spp.) as a substitute for pathogen inoculation or field screening. A bioassay of grape leaves with culture filtrates from the pathogen showed that their phytotoxicities were active and host-selective. Ethyl acetate extracts from them also showed toxicities and host selectivity in both bunches of grapes and muscadine grapes. The sensitive range of plants to the culture filtrates and their ethyl acetate extracts was consistent with the host range of the Pierce's disease pathogen. Susceptible cultivars are sensitive to even highly diluted culture filtrates, while resistant cultivars were not affected even at their original culture filtrates. Susceptible cultivars were more sensitive to the undiluted culture filtrate than were highly diluted culture filtrates, and the younger leaves were the most sensitive to the culture filtrates in grapes. Although some European grape cultivars showed moderately susceptibility in this study, the determination of varietal resistance to Pierce's disease by the treatment of culture filtrates of pathogens could provide valuable information for the preliminary selection of genetic resources and seedlings from hybridization in a disease resistant grape breeding program.

• Korean Journal of Social Welfare
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• v.62 no.4
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• pp.149-170
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• 2010

The purpose of this study to develop a human rights education program for improving human rights sensitivity of the teachers in community child center, and verify its effectiveness. For this purpose, pre-program and post-program analysis was conducted by using human rights sensitivity scale on 102 teachers working in community child center. The major results of this study is as follows: First, the teachers' human rights sensitivity was statistically improved. Second, the teachers' ability of situation perception, ability of consequence perception, and ability of consequence perception were statistically improved. Third, the teachers' human rights sensitivity on "the right not to be arrested illegally", "physical liberty of the disabled", "the right to labor by migrant workers", and "freedom from detention" was statistically improved. Based on the research results, practical implications and limitations were discussed for developing human rights education program.