• Journal of Microbiology
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• v.39 no.1
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• pp.62-66
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• 2001

Unlike eukaryotic efflux pumps energized by ATPase bacterial efflux pumps are energized by the proton motive force. That is the reason why CCCP, an inhibitor of proton motive forcer is widely used to study the bacterial efflux pump. In many cases, efflux systems have been observed only in quinolone-resistant bacteria. Most of the quinolone-susceptible strains have been found to maintain little efflux pump. However some susceptible bacteria skewed the increased intracellular quinolone concentration only at a low concentration (0.01 or 0.1 mM) but net at a high concentration (1 mM) of CCCP. If bacterial cells were killed at high concentrations of CCCP and lost the integrity of their membranes, the intracellular quinolone would leak out from cells with no efflux system. The efflux pump system in the quinolone-susceptible strains could net be detected at the same concentration used for resistant bacteria. To test this hypothesist the intracellular quinolone concentration in the quinolone-susceptible and -resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was assayed at various concentrations of CCCP. Since the effect of CCCP is very rapid, the survival of bacteria was observed by assaying the DNA synthesis in 5 min. In the case of E. coli, but not P. aeruginosa or S. aureus, the quinolone susceptible strain was more susceptible to CCCP than the quinolone resistant ones, especially when the incubation with CCCP was extended. Decrease of the intracellular quinolone concentration resulted in a false result-no or weak efflux system in the quinolone susceptible strains. Results suggested that the concentration of CCCP should be optimized in order to detect the efflux system in the quinolone susceptible strains of E. coli.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.132-139
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• 2015

Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.

• Geomechanics and Engineering
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• v.30 no.4
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• pp.393-399
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• 2022

The Segregation Potential (SP) is one of the most widely used predictors of frost heave in cold regions. Laboratory step-freezing tests determining a representative SP at the onset of the formation of the last ice lens (near the thermal steady state condition) can predict susceptibility to frost heave. Previous work has proposed empirical semi-log fitting for determination of the representative SP and applied it to several fine-grained soils, but considering only frost-susceptible soils. The presence of fines in coarse-grained soil affects frost susceptibility. Therefore, it is required to evaluate the applicability of the empirical semi-log fitting for both frost-susceptible and non-frost-susceptible soils with fines content. This paper reports laboratory frost heave tests for fines contents of 5%-70%. The frost susceptibility of soil mixtures composed of sand and silt was classified by the representative SP, and the suitability of the empirical semi-log fitting method was assessed. Combining semi-log fitting with simple laboratory frost heave testing using a temperature-controllable cell is shown to be suitable for both frost-susceptible and non-frost-susceptible soils. In addition, initially non-frost-susceptible soil became frost susceptible at a 10%-20% weight fraction of fines. This threshold fines content matched well with transitions in the engineering characteristics of both the unfrozen and frozen soil mixtures.

• 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 Child Studies
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• v.25 no.4
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• pp.17-32
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• 2004

Factor analysis of data collected from 336 elementary school children provided difficuitness and susceptibility as the temperament factors, and affect and control as the nurturing factors. Results showed that non-susceptible children with low controlling mother perceived their cognitive competence positively while highly susceptible children showed no differences in their self-competence by mothers' controlling behavior. Perceived cognitive competence of susceptible boys and of susceptible 3rd graders were low when their mothers asserted low control. Thus, mothers' controlling behavior supported perceived cognitive competence in highly susceptible boys and 3rd graders. That is, the effect of mother's behavior on child's self-competence was moderated by child's characteristics. These results partially supported the Conditional Model.

• The Journal of the Korean Society for Microbiology
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• v.9 no.1
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• pp.19-24
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• 1974

During March to October 1973 at National Medical Center, one thousand four hundred sixty four pathogens that exclude penicillin sensitive organisms such as gonococcus, pneumococcus, streptococcus; ampicillin sensitive H. influenzae and gentamicin sensitive pseudomonas spp, were isolated. These strains identified as follows: Sta. aureus 399 E. coli 359 Sta. epidermidis 183 Klebsiella spp 171 Proteus spp 103 B. anitratum 80 Salmonella spp 68 Enterococcus 53 Shigella spp 48 In general, Sta. epidermidis is regarded as nonpathogen, however, author included pure culture of this bacteria in this study. 1. High susceptibility to staphylococcus reveals cephalosporin, methicillin, gentamicin & leucomycin. 2. Ampicillin is only one susceptible antibiotic to Enterococcus. 3. Cephalosporin and gentamicin reveal susceptible antibiotics to E. coli. 4. Gentamicin is only one susceptible antibiotic to Klebsiella spp. 5. Gentamicin & carbenicillin reveal moderately susceptible antibiotics to Proteus spp. 6. There is no susceptible antibiotic to B. anitratum. 7. About thirty percent strains of salmonella are resistant to chloramphenicol. 8. Carbenicillin, cephalosporin & gentamicin reveal susceptible to shigella spp. 9. Multiple resistant rate to more than two antibiotics which includes tetracycline are as follows. Sta. aureus 56.5% E. coli. 80.9% Shigella spp 93.8%

• The KSFM Journal of Fluid Machinery
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• v.10 no.5
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• pp.20-26
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• 2007

Some gate valves are susceptible to pressure locking and thermal binding which prevent the safety function. The safety related gate valves susceptible to pressure locking and thermal binding shall be identified and taken preventive actions to ensure the safety function. The identification of the gate valves susceptible to pressure locking and thermal binding needs the evaluation of system design, valve and piping arrangement, test requirements, and operating conditions. Application of preventive methods should consider the system safety function, applicability, effectiveness, interface with system design, and cost. The selection procedure of valves susceptible to pressure locking and thermal binding can be effectively used in industry including nuclear power plants. In order to prevent the pressure locking, the hole can be drilled through the one disc of upstream side or down stream and the external equalizing line can be installed from bonnet to downstream or upstream. The double disc parallel seat valve type can be used instead of flexible wedge gate valve to prevent the thermal binding. The identification of gate valves susceptible to pressure locking and thermal binding, and preventive actions will meet the regulatory requirements and enhance the availability and safety of plants.

• Journal of Microbiology
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• v.40 no.2
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• pp.98-103
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• 2002

Twenty-eight clinical isolates of Escherichia coil, composed of thirteen norfloxacin resistant isolates (MIC of >16${\mu}$g/ml), one intermediately resistant isolate (MIC of 8${\mu}$g/ml), and fourteen susceptible isolates (MIC of <4${\mu}$g/ml), were randomly selected to study the norfloxacin resistance mechanism and phylogeny in clinical isolates in Korea. Eleven nofloxacin resistant isolates and one susceptible isolate were multi-drug resistant (MDR). Every norfloxacin resistant isolate with MIC higher than 32${\mu}$g/ml had the same three mutations: Ser83\longrightarrowLeu and Asp87\longrightarrowAsn or Tyr in GyrA and Ser80\longrightarrowIle in ParC. Whereas a resistant isolate with MIC of 16${\mu}$g/ml had three mutations but Asp87 in GyrA was replaced with Gly instead of Asn. The intermediately resistant isolate had the same two mutations in GyrA but a different mutation in ParC, Glu84\longrightarrowLys. Among the susceptible isolates, two isolates with MIC of 4${\mu}$g/ml had one mutation: Ser83\longrightarrowiLeu in GyrA, and no mutation was found in the susceptible isolates. Resistant isolates showed higher efflux activity than the susceptible ones, with random amplification of polymorphic DNA (RAPD), six susceptible isolates form a separate group from the rest of the isolates.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.327-336
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• 1996

This study was conducted to investigate the content of antioxidant and GST activity of the oxyfluorfen-tolerant and -susceptible rice cultivars with barnyardgrass, a typical susceptible weed in accordance by oxyfluorfen treatment. The content of vitamin C was higher in the tolerant rice cultivar than in the susceptible rice cultivar and barnyardgrass. The contents of vitamin E, carotenoid, glutathione(GSH, GSSG, total glutathione) were not different between the tolerant and susceptible plants. In the case of the content of vitamin C due to the treatment of oxyfluorfen, the tolerant rice cultivars, Hawon and Baru decreased less than the susceptible rice cultivars and barnyardgrass. After the treatment of oxyfluorfen the contents of vitamin E and GSH in the tolerant rice cultivars were higher than in the susceptible rice cultivars or barnyardgrass. But in the content of carotenoid was greater in the tolerant rice cultivars than in the susceptible rice cultivars but they didn`t have any difference in comparison with the susceptible barnyardgrass. And there was no difference in the content of GSSG between the tolerant and susceptible plants. When CDNB or oxyfluorfen were used as substrate, the GST activity, was higher in the tolerant rice cultivars than in the susceptible rice cultivars or batnyardgrass. After the treatment of oxyfluorfen the GST activity was not induced in the rice, but was induced in the barnyardgrass. Even after the treatment of acifluorfen, bifenox and oxadiazon the GST activity was not induced in the rice cultivars.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.54-63
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• 1996

This study was conducted to investigate the anatomical and ultrastructural responses of the oxyfluorfen-tolerant and -susceptible rice cultivars with barnyardgrass, a typical susceptible weed by oxyfluorfen and the herbicides having similar mode of action treatment. After the treatment of $10^{-5}M$ oxyfluorfen, the tolerant rice cultivars no showed the structural damage of leaf surface, but the susceptible rice cultivate was damaged in the wax and the susceptible barnyardgrass was even destroyed in the tissue irregularly. Also in the susceptible rice cultivars and barnyardgrass the thickness of leaf blade was greatly decreased. The anatomical change was not observed in the tolerant rice cultivars but epidermal cells, mesophyll cells and bundle sheath cells were badly broken in the susceptible rice cultivars and barnyardgrass and especially after 24 hours of the treatment the structure of susceptible rice cultivars was completely disintegrated. The irregularity of chloroplast shape and the distortion of chloroplast envelope were generally observed and the starch tended to decrease by oxyfluorfen treatment regardless of rice cultivars. Such a structural damage were appeared more badly in the susceptible rice cultivars and bamyardgrass than in the tolerant rice cultivars. By the treatment of diphenyl ether herbicides, the thickness of leaf blade greatly reduced in the order of oxyfluorfen > acifluorfen > bifenox > oxadiazon, and the susceptible rice cultivars showed more reduction than the tolerant rice cultivars. Especially, the susceptible rice cultivars showed that the leaf structure was badly broken down with damage epidermal cells and bundle sheath cells.