• Title/Summary/Keyword: Co tolerance

Search Result 441, Processing Time 0.025 seconds

Tolerance: An Ideal Co-Survival Crop Breeding System of Pest and Host in Nature with Reference to Maize

  • Kim, Soon-Kwon
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.45 no.1
    • /
    • pp.59-70
    • /
    • 2000
  • In nature, plant diseases, insects and parasites (hereafter called as "pest") must be co-survived. The most common expression of co-survival of a host crop to the pest can be tolerance. With tolerance, chemical uses can be minimized and it protects environment and sustains host productivity and the minimum pest survival. Tolerance can be applicable in all living organisms including crop plants, lifestocks and even human beings. Tolerant system controls pest about 90 to 95% (this pest control system often be called as horizontal or partial resistance), while the use of chemicals or selection of high resistance controls pest 100% (the most expression of this control system is vertical resistance or true resistance). Controlling or eliminating the pests by either chemicals or vertical resistance create new problems in nature and destroy the co-survial balance of pest and host. Controlling pests through tolerance can only permit co-survive of pests and hosts. Tolerance is durable and environmentally-friend. Crop cultivars based on tolerance system are different from those developed by genetically modified organism (GMO) system. The former stabilizes genetic balance of a pest and a host crop in nature while the latter destabilizes the genetic balance due to 100% control. For three decades, the author has implemented the tolerance system in breeding maize cultivars against various pests in both tropical and temperate environments. Parasitic weed Striga species known as the greatest biological problem in agriculture has even been controlled through this system. The final effect of the tolerance can be an integrated genetic pest management (IGPM) without any chemical uses and it makes co-survival of pests in nature.in nature.

  • PDF

Application of the Combination of Soybean Lecithin and Whey Protein Concentrate 80 to Improve the Bile Salt and Acid Tolerance of Probiotics

  • Gou, Xuelei;Zhang, Libo;Zhao, Shiwei;Ma, Wanping;Yang, Zibiao
    • Journal of Microbiology and Biotechnology
    • /
    • v.31 no.6
    • /
    • pp.840-846
    • /
    • 2021
  • To improve the bile salt and acid tolerance of probiotics against gastrointestinal stresses, we investigated the effects of soybean lecithin and whey protein concentrate (WPC) 80 on the bile salt tolerance of Lacticaseibacillus paracasei L9 using a single-factor methodology, which was optimized using response surface methodology (RSM). The survival rate of L. paracasei L9 treated with 0.3% (w/v) bile salt for 2.5 h, and combined with soybean lecithin or WPC 80, was lower than 1%. After optimization, the survival rate of L. paracasei L9 incubated in 0.3% bile salt for 2.5 h reached 52.5% at a ratio of 0.74% soybean lecithin and 2.54% WPC 80. Moreover, this optimized method improved the survival rate of L. paracasei L9 in low pH condition and can be applied to other lactic acid bacteria (LAB) strains. Conclusively, the combination of soybean lecithin and WPC 80 significantly improved the bile salt and acid tolerance of LAB. Our study provides a novel approach for enhancing the gastrointestinal tolerance of LAB by combining food-derived components that have different properties.

Effects of NO and $SO_2$ on Growth of $Highly-CO_2-Tolerant$ Microalgae

  • Lee, Jung-Hwa;Lee, Jin-Suk;Shin, Chul-Seung;Park, Soon-Chul;Kim, Seung-Wook
    • Journal of Microbiology and Biotechnology
    • /
    • v.10 no.3
    • /
    • pp.338-343
    • /
    • 2000
  • The growth capabilities of three $highly-CO_2-tolerant$ microalgae under high concentrations of $CO_2$ were compared for their tolerance to $SO_2$ and NO, the major inhibitory compounds present in flue gases. Although all strains showed good growth with 15% $CO_2$, Chlorella KR-1 exhibited the most desirable properties for $CO_2$ fixation among the strains compared. While Chlorella sp. HA-1 exhibited the best tolerance to NO among the other strains tested, Chlorella sp. KR-1 showed higher tolerance to $SO_2$ than the other two strains tested.

  • PDF

Noise Evaluation Considering the Uncertainty Variation According to Frequency

  • Lee, Chulwon;Koo, SeungJun;Kong, Young Mo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2014.04a
    • /
    • pp.191-196
    • /
    • 2014
  • In the evaluation of measured noise data, tolerance shall be decided based on the uncertainty. The uncertainty has frequency variations due to the different standard deviations at each frequency. Therefore, tolerance shall be differently decided for each frequency with the same confidence probability. In the report, the evaluation method considering the frequency variation of uncertainty will be introduced. From the approach, considering the actual noise distribution characteristics of the ships, the tolerance shall be decided for each frequency with the same probability, but the overall averaged value shall be kept to the value designated in each notation.

  • PDF

CO Tolerance Improvement of MEA Using Metal Thin Film by Sputtering Method in PEM Fuel Cell (스퍼터링 공정으로 제조된 금속박막을 이용한 고분자전해질 연료전지 막-전극접합체의 일산화탄소에 대한 내구성 연구)

  • Cho, Yong-Hun;Yoo, Sung-Jong;Cho, Yoon-Hwan;Park, Hyun-Seo;Sung, Yung-Eun
    • Journal of the Korean Electrochemical Society
    • /
    • v.10 no.4
    • /
    • pp.279-282
    • /
    • 2007
  • When reformer for fuel cell is used, CO in hydrogen gas leads to a seriously decreased membrane electrode assembly (MEA) performance by catalyst poisoning. The effect of CO on performance of modified MEA by sputtering method is studied in this paper. The experimental results show that sputtered Pt and Ru thin film improve a single cell performance of MEA and sputtered metal thin film has a CO tolerance. The air injection process on anode show improved CO tolerance test result. Moreover, Pt, Ru and PtRu thin film by sputtering had influence on the CO tolerance with air injection process.

Nitric Oxide and Hydrogen Peroxide Production are Involved in Systemic Drought Tolerance Induced by 2R,3R-Butanediol in Arabidopsis thaliana

  • Cho, Song-Mi;Kim, Yong Hwan;Anderson, Anne J.;Kim, Young Cheol
    • The Plant Pathology Journal
    • /
    • v.29 no.4
    • /
    • pp.427-434
    • /
    • 2013
  • 2R,3R-Butanediol, a volatile compound produced by certain rhizobacteria, is involved in induced drought tolerance in Arabidopsis thaliana through mechanisms involving stomatal closure. In this study, we examined the involvement of nitric oxide and hydrogen peroxide in induced drought tolerance, because these are signaling agents in drought stress responses mediated by abscisic acid (ABA). Fluorescence-based assays showed that systemic nitric oxide and hydrogen peroxide production was induced by 2R,3R-butanediol and correlated with expression of genes encoding nitrate reductase and nitric oxide synthase. Co-treatment of 2R,3R-butanediol with an inhibitor of nitrate reductase or an inhibitor of nitric oxide synthase lowered nitric oxide production and lessened induced drought tolerance. Increases in hydrogen peroxide were negated by co-treatment of 2R,3R-butanediol with inhibitors of NADPH oxidase, or peroxidase. These findings support the volatile 2R,3R-butanediol synthesized by certain rhizobacteria is an active player in induction of drought tolerance through mechanisms involving nitric oxide and hydrogen peroxide production.

The Development of Tolerance to and Dependence on Morphine are Reduced by Co-administration of Nalbuphine in Rat (Nalbuphine의 병용투여에 의한 morphine의 내성 및 의존성 형성 저하효과)

  • 정면우;임화경;전용준;김혜정;박인숙;오우용;왕소영;박윤주;강주희
    • YAKHAK HOEJI
    • /
    • v.46 no.4
    • /
    • pp.276-282
    • /
    • 2002
  • Morphine has been used widely on the treatment of many types of chronic pain. However the development of tolerance to morphine by repeat application is a major problem in pain therapy. The purpose of the present study was to investigate whether combined administration of nalbuphine with morphine affects the development of tolerance to and dependence on morphine. We hypothesize that the use of nalbuphine, k-agonist may prove to be useful adjunct therapy to prevent morphine-induced undesirable effects in the management of some forms of chronic pain. Morphine (10 mg/kg) was injected to rats intraperitoneally for 5 days. The variable dose of nalbuphine (0.1, 1.0 and 5.0 mg/kg) was administered (i.p.) in combination with morphine injection. The development of tolerance to morphine was assessed by measuring the antinociceptive effect with the Randall-Selitto apparatus. The development of dependence on morphine was determined by the scoring the precipitated withdrawal signs for 20 min after injection of naloxone (10 mg/kg, i.p.). Nalbuphine did not attenuate antinociceptive effect of morphine in rats. Interestingly, combined administration of morphine with nalbuphine (100:1) significantly attenuated the development of morphine tolerance and dependence. These results suggest that the co-administration of nalbuphine with morphine in chronic morphine treatment can be one of therapies to reduce the development of dependence on morphine.

Screening of Cholesterol-lowering Bifidobacterium from Guizhou Xiang Pigs, and Evaluation of Its Tolerance to Oxygen, Acid, and Bile

  • Zhang, Rujiao;He, Laping;Zhang, Ling;Li, Cuiqin;Zhu, Qiujin
    • Food Science of Animal Resources
    • /
    • v.36 no.1
    • /
    • pp.37-43
    • /
    • 2016
  • Cardiovascular and cerebrovascular diseases seriously harm human health, and Bifidobacterium is the most beneficial probiotic in the gastrointestinal tract of humans. This work aimed to screen cholesterol-lowering Bifidobacterium from Guizhou Xiang Pig and evaluate its tolerance to oxygen, acid, and bile. Twenty-seven aerotolerant strains with similar colony to Bifidobacterium were isolated through incubation at 37℃ in 20% (v/v) CO2-80% (v/v) atmospheric air by using Mupirocin lithium modified MRS agar medium, modified PTYG with added CaCO3, and modified PTYG supplemented with X-gal. Ten strains with cholesterol-lowering rates above 20% (w/w) were used for further screening. The selected strains’ tolerance to acid and bile was then determined. A combination of colony and cell morphology, physiological, and biochemical experiments, as well as 16S rRNA gene-sequence analysis, was performed. Results suggested that BZ25 with excellent characteristics of high cholesterol-removal rate of 36.32% (w/w), as well as tolerance to acid and bile, was identified as Bifidobacterium animalis subsp. lactis. To further evaluate Bifidobacterium BZ25’s growth characteristic and tolerance to oxygen, culture experiments were performed in liquid medium and an agar plate. Findings suggested that BZ25 grew well both in environmental 20% (v/v) CO2-80% (v/v) atmospheric air and in 100% atmospheric air because BZ25 reached an absorbance of 1.185 at 600 nm in 100% atmospheric air. Moreover, BZ25 was aerotolerant and can grow in an agar medium under the environmental condition of 100% atmospheric air. This study can lay a preliminary foundation for the potential industrial applications of BZ25.

Study of the Assembly of Indoor Air-conditioner Unit Using Tolerance Analysis (공차해석을 이용한 에어컨 실내기의 조립성에 관한 연구)

  • Kim, Cheulgon;Hwang, Jihoon;Seo, Hyeongjoon;Mo, Jinyong;Jung, Duhan;Hong, Seokmoo
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.39 no.4
    • /
    • pp.423-428
    • /
    • 2015
  • To identify locations and causes of interference among parts of an indoor air-conditioning unit, a 3D tolerance analysis was performed and optimized with respect to assembly gaps and the tolerance of each part. The maximum value of the defect rate resulting from the tolerance analysis was found to be 72.6 at the assembly portion of the body and drain. The maximum displacement caused by the thermal deformation during a heating operation was calculated to be approximately 1 mm by using finite element analysis (FEA). Therefore, it is possible that an interference among the assembled parts occurs. The tolerance of the drain was modified by the results of the sensitivity analysis. As a result, the defect rate was greatly reduced to 0.03. Through the FEA results of the indoor air-conditioning unit, it was shown that the improved tolerance of the drain decreased the interference among the assembled parts even though thermal deformation occurs during operation.

Probiotic Properties of Bifidobacteria Isolated from Feces of Infants (유아 분변에서 분리한 비피도박테리아의 프로바이오틱스 기능성 연구)

  • Kang, Chang-Ho;Kim, YongGyeong;Han, Seul Hwa;Jeong, Yulah;Park, HyeMin;Paek, Nam-Soo
    • Journal of Dairy Science and Biotechnology
    • /
    • v.37 no.1
    • /
    • pp.40-48
    • /
    • 2019
  • Bifidobacteria are a prototype probiotic, which normally inhabit the intestinal tract of humans. In the present study, four species of Bifidobacterium isolated from the feces of infants were characterized. The tolerance for acid or bile salt, autoaggregation, and antibiotic resistance of the bacteria were examined. The four species were resistant to low pH, bile salts, and up to 3% bile acid. Autoaggregation rates were as high as 90%. The bacteria were consistently resistant to gentamicin, kanamycin, streptomycin, ciprofloxacin, and nalidixic acid. Due to their tolerance to environmental factors like acid and bile salts, B. longum MG723, B. breve MG729, B. bifidum MG731, and B. animalis subsp. lactis MG741 are potentially valuable as probiotics and may be useful for industrial application.