• Title/Summary/Keyword: On Resistance

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Different Mechanisms of Induced Systemic Resistance and Systemic Acquired Resistance Against Colletotrichum orbiculare on the Leaves of Cucumber Plants

  • Jeun, Yong-Chull;Park, Kyung-Seok;Kim, Choong-Hoe
    • Mycobiology
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    • v.29 no.1
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    • pp.19-26
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    • 2001
  • Defense mechanisms against anthracnose disease caused by Colletotrichum orbiculare on the leaf surface of cucumber plants after pre-treatment with plant growth promoting rhizobacteria(PGPR), amino salicylic acid(ASA) or C. orbiculare were compared using a fluorescence microscope. Induced systemic resistance was mediated by the pre-inoculation in the root system with PGPR strain Bacillus amylolquefaciens EXTN-1 that showed direct antifungal activity to C. gloeosporioides and C. orbiculare. Also, systemic acquired resistance was triggered by the pre-treatments on the bottom leaves with amino salicylic acid or conidial suspension of C. orbiculare. The protection values on the leaves expressing SAR were higher compared to those expressing ISR. After pre-inoculation with PGPR strains no change of the plants was found in phenotype, while necrosis or hypersensitive reaction(HR) was observed on the leaves of plants pre-treated with ASA or the pathogen. After challenge inoculation, inhibition of fungal growth was observed on the leaves expressing both ISR and SAR. HR was frequently observed at the penetration sites of both resistance-expressing leaves. Appressorium formation was dramatically reduced on the leaves of plants pre-treated with ASA, whereas EXTN-1 did not suppress the appressorium formation. ASA also more strongly inhibited the conidial germination than EXTN-1. Conversely, EXTN-1 significantly increased the frequency of callose formation at the penetration sites, but ASA did not. The defense mechanisms induced by C. orbiculare were similar to those by ASA. Based on these results it is suggested that resistance mechanisms on the leaf surface was different between on the cucumber leaves expressing ISR and SAR, resulting in the different protection values.

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A Study on Test Methods for Performance Appraisal of Root Barrier Appling to Green Roofs (옥상 및 인공지반녹화용 방근재의 성능기준 설정을 위한 방근성 시험방법에 관한 연구)

  • Oh, Sang-Keun;Kwak, Kyu-Sung;Sun, Yoon-Suk;Kwon, Shi-Won
    • Journal of the Korea Institute of Building Construction
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    • v.7 no.1 s.23
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    • pp.79-84
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    • 2007
  • Selection of proper root barrier as destination part of greening is very important in Root penetration resistance plan. To select proper root barrier, it need to understand composition of greening part, size, kind of plant, connection with waterproofing layer. In this point of view, we have establish greening on the roof or concrete structure, not been understand the structural mechanism. It means that we misunderstood about purpose of greening and using it. So, chosen materials and construction method was not proper for greening, it caused water leakage and decrease performance of concrete structure. Therefore, we would suggest 5 items of test methods considering environmental condition for green roof. Watertightness by water of greening part, root penetration resistance test by root penetration, bacteria resistance by must or bacteria in soil, chemical resistance by rain and chemical agent of fertilizer, and load resistance by soil depth, size of plant. These suggested test methods could be referred as guideline to test in green roof system because of not exist any performance appraisal guideline or standard. Consequently, it should be analysis as technical and institutional subdividing test methods and it need to study constantly as varied angles.

A Study on the Variation Characteristics of Ground Resistance According to Ground Parameters (대지파라미터에 따른 접지저항의 변동 특성에 관한 연구)

  • Han, Ki-Boong;Jeong, Se-Joong;Lee, Dae-Jong;Lee, Sang-Ick
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.434-436
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    • 2000
  • It is difficult to accurately measure the ground resistance because it varies widely not only with the type of soil but also with the ground parameters; the moisture, the temperature the buried depth of electrodes, and the ground augmentation material and so on. Therefore, in this paper we analyzed the relation between the parameters and the resistance of ground in order to obtain a method of maintaining ground resistance stable. In experiments, the variation coefficients of ground resistance were calculated by the monthly measured data. The ground resistance decreases as the length of the ground rod increases. The variation between the ground resistance and the moisture rate of soil was low in case of using the ground augmentation material. Without the ground augmentation material, the ground resistance decreases as the moisture rate of soil increases. The ground resistance becomes small when the earth temperature becomes low.

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Genetics of Fusarium Wilt Resistance in Pigeonpea (Cajanus cajan) and Efficacy of Associated SSR Markers

  • Singh, Deepu;Sinha, B.;Rai, V.P.;Singh, M.N.;Singh, D.K.;Kumar, R.;Singh, A.K.
    • The Plant Pathology Journal
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    • v.32 no.2
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    • pp.95-101
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    • 2016
  • Inheritance of resistance to Fusarium wilt (FW) disease caused by Fusarium udum was investigated in pigeonpea using four different long duration FW resistant genotypes viz., BDN-2004-1, BDN-2001-9, BWR-133 and IPA-234. Based on the $F_2$ segregation pattern, FW resistance has been reported to be governed by one dominant gene in BDN-2004-1 and BDN-2001-9, two duplicate dominant genes in BWR-133 and two dominant complimentary genes in resistance source IPA-234. Further, the efficacy of six simple sequence repeat (SSR) markers namely, ASSR-1, ASSR-23, ASSR-148, ASSR-229, ASSR-363 and ASSR-366 reported to be associated with FW resistance were also tested and concluded that markers ASSR-1, ASSR-23, ASSR-148 will be used for screening of parental genotypes in pigeonpea FW resistance breeding programs. The information on genetics of FW resistance generated from this study would be used, to introgress FW resistance into susceptible but highly adopted cultivars through marker-assisted backcross breeding and in conventional breeding programs.

Antimicrobial Resistance and Multi-Drug Resistance Patterns of Pathogenic Bacteria Isolated from Food Poisoning Patients in Incheon (인천지역 식중독 환자에서 분리한 병원성 세균의 항생제 내성 및 다제 내성 양상)

  • Huh, Myung-Je;Oh, Sung-Suck;Jang, Jae-Seon
    • The Korean Journal of Food And Nutrition
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    • v.26 no.1
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    • pp.132-136
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    • 2013
  • Antimicrobial resistance and multi-drug resistance patterns have been carried out on total of 210 isolated of Salmonella spp. and pathogenic E. coli isolated from food poisoning patients on January through December 2012 in Incheon, Korea. The highest percentage of antibiotics resistance was found to the following antimicrobial agents: tetracycline 43.8%, ampicillin 34.8%, nalidixic acid 23.8%, sulfamethoxazole/trimethoprim and chloramphenicol 12.4%, and ampicillin/sulbactam 11.4%. The highest percentage of resistance was 37.5% to ampicillin for Salmonella spp. and 59.0% to tetracycline for pathogenic E. coli. Overall the multidrug resistance rates of 1 drug was 26.2%, 2 drugs 9.0%, 3 drugs 9.5%, 4 drugs 7.1%, and 5 or more drugs 12.46%. The multi-drug (MDR) strains to four or more antimicrobial agents among the resistant organisms were quite high: 15.9% and 22.1% for Salmonella spp. and pathogenic E. coli, respectively. The study implies that limitation of unnecessary medication use is pertinent in order to maintaining the efficacy of drugs.

A Study on the Performance Appraisal for Copper Sheet as Root Barrier Material Appling to Green Roof System (옥상녹화 및 인공지반녹화용 구리시트 방근재의 성능평가에 관한 연구)

  • Cho, Il-Kyu;Kwon, Shi-Won;Kwak, Kyu-Sung;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.04a
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    • pp.5-8
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    • 2007
  • Selection of proper root barrier as destination part of greening is very important in Root penetration resistance plan. To select proper root barrier, it need to understand composition of greening part, size, kind of plant, connection with waterproofing layer. In this point of view, we have establish greening on the roof or concrete structure, not been understand the structural mechanism. It means that we misunderstood about purpose of greening and using it. So, chosen materials and construction method was not proper for greening, it caused water leakage and decrease performance of concrete structure. Therefore, we examine the practical use of copper sheet considering environmental condition for green roof. Watertightness by water of greening part, root penetration resistance test by root penetration, bacteria resistance by must or bacteria in soil, chemical resistance by rain and chemical agent of fertilizer, and load resistance by soil depth, sire of plant. These suggested test methods could be referred as guideline to test in green roof system because of not exist any performance appraisal guideline or standard. Consequently, it should be analysis as technical and institutional subdividing test methods and it need to study constantly as varied angles.

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The Parameter Study on the Characteristics of Axial Force in Turnout with Continuous Welded Rail (분기부(分岐部) 장대(長大)레일화시의 축력거동특성(軸力擧動特性) 해석(解析))

  • Kim, Doo-Hwan;Ko, Sang-Hun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.2
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    • pp.163-174
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    • 2001
  • This paper is to study the characteristics of axial force behavior that operates to the part of turnout when it makes the turnout and the continuous welded rail unifying. The study is to model by using the 50kgN rail No. 15 turnout used in the domestic national railway and the UIC60 rail No. 18 turnout used in the rapid transit railway as the finite elements for analyzing the axial force behavior of the turnout by the continuous welded rail. It is to analyze the characteristics of behavior according to the change of creep resistance, ballast resistance and the change of parameter valuables of heel joint by the axial force simulation in making the continuous welded rail and then, it is to present the result. As the result of research on the parameter valuables through the analysis, it shows that the maximum axial force of turnout by the continuous welded rail are largely subordinated to the maximum resistance of heel joint and the fitting devices than the ballast resistance. Also it shows that the maximum axial force produced changes a lot according to the characteristics of creep resistance of the fitting part and the ballast resistance.

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Study of Seismic Resistance Performance Evaluation Method for Existing Mid-Low Story RC Structure Buildings by Applying Fuzzy Theory (퍼지이론을 적용한 기존 중저층 철근콘크리트 건축물의 내진성능평가기법 연구)

  • Kim, Dong-Hee;Kim, Hyun-Su
    • Journal of Korean Association for Spatial Structures
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    • v.17 no.2
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    • pp.53-62
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    • 2017
  • This study aims to establish a seismic resistance performance evaluation method that makes sure to secure the seismic resistance performance of the existing mid-low story reinforced concrete structures. This study focuses on the development of the seismic resistance performance evaluation method for the overall seismic resistance performance evaluation on the buildings by applying fuzzy theory. This seismic resistance performance evaluation method considers the mutual relations among the type of force, the type of member, the type of story, and the states of deterioration of the buildings. The total seismic resistance performance index from this method was calculated by the intensity weight of each evaluation item, fuzzy measure, fuzzy integration. Moreover, the evaluation methodology was established in this study to identify the performance level of the Immediate Occupancy, Life Safe, Collapse Prevention by applying the fuzzy theory.

Inheritance of Cyst Nematode Resistance in a New Genetic Source, Glycine max PI 494182

  • Arelli, Prakash R.;Wang, Dechun
    • Journal of Crop Science and Biotechnology
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    • v.11 no.3
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    • pp.177-180
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    • 2008
  • Worldwide, cyst nematode(Heterodera glycines Ichinohe) is the most destructive pathogen of cultivated soybean. In the USA, current annual yield losses are estimated to be nearly a billion dollars. Crop losses are primarily reduced by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars over time because resistance primarily traces to two soybean accessions. It is important to use diverse resistance sources to develop new nematode resistant cultivars. Soybean PI 494182 is a recent introduction from Japan and found to be resistant to multiple nematode populations. It is yellow seeded and maturity group 0. We have determined inheritance of resistance in PI 494182 using $F_{2:3}$ families derived from cross PI 494182 X cv. Skylla. Skylla is a susceptible parent. Three nematode populations, races 1, 3, and 5, corresponding to HG types 2.5.7, 0, and 2.5.7 were used to bioassay 162 $F_{2:3}$ families in greenhouse experiments. Based on Chi-square tests, a two-gene model is proposed for resistance to race 1 and a three-gene model is proposed for conditioning resistance to both races 3 and 5. Correlation coefficient analysis indicated that some genes conditioning resistance to races 1, 3, and 5 are shared or closely linked with each other. These results will be useful to soybean breeders for developing soybean cultivars for broad resistance to nematodes.

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Effects of Elastic Resistance Training on Biomechanical Ability in College Taekwondo Athletes

  • Hyun Suk Yang;Jonggeun Woo;Jiheon Hong
    • The Journal of Korean Physical Therapy
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    • v.35 no.5
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    • pp.132-138
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    • 2023
  • Purpose: This study compared the effects of the elastic resistance and general training for college Taekwondo athletes, and investigated the biomechanical ability and lower extremity function according to the movement speed of the knee joint. Methods: Twenty university student Taekwondo athletes participated voluntarily in this study. The subjects performed general resistance training for four weeks, followed by elastic resistance training for another four weeks. The biomechanical parameters during the fast and slow isokinetic conditions, Y-balance ability, and vertical jump ability were measured three times: before training, after general resistance training, and after elastic resistance training. Statistical analysis was performed under isokinetic conditions and the intervention effect. Results: The biomechanical ability differed significantly between fast and slow isokinetic conditions (p<0.05). An analysis of the training method revealed a significant difference in the maximum knee extension speed and the posterior-lateral direction of the Y-balance test (p<0.05). Conclusion: Elastic resistance training had a more positive effect on the functional task performance than biomechanical factors related to muscular strength compared to general resistance training. In addition, speed-related knee biomechanical information of subjects with strong physical abilities could be utilized in sports physiotherapy.