• 제목/요약/키워드: Co tolerance

검색결과 441건 처리시간 0.03초

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

  • Kim, Soon-Kwon
    • 한국작물학회지
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    • 제45권1호
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    • pp.59-70
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    • 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.

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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
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    • 제31권6호
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    • pp.840-846
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    • 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
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    • 제10권3호
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    • pp.338-343
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    • 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.

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Noise Evaluation Considering the Uncertainty Variation According to Frequency

  • Lee, Chulwon;Koo, SeungJun;Kong, Young Mo
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 춘계학술대회 논문집
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    • pp.191-196
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    • 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.

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

  • 조용훈;유성종;조윤환;박현서;성영은
    • 전기화학회지
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    • 제10권4호
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    • pp.279-282
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    • 2007
  • 개질기에서 생산된 수소를 연료전지용 연료로 사용할 때에는 개질수소가 포함하고 있는 일산화탄소가 막-전극접합체의 촉매를 피독시켜서 연료전지 성능이 크게 감소된다. 본 논문에서는 개질수소에 포함된 일산화탄소가 스퍼터링 공정으로 제조된 박막층에 의하여 개선된 막-전극접합체의 성능에 어떠한 영향을 미치는지 연구하였다. 실험결과 Pt와 Ru박막은 MEA의 단위전지 성능을 개선하였으며, 금속박막은 막-전극접합체의 일산화탄소에 대한 내구성을 증가시켰다. 산화전극으로의 공기주입 운전기법은 막-전극접합체의 일산화탄소에 대한 내구성을 증가시켰다. 게다가 Pt, Ru그리고 PtRu박막은 공기주입 운전에 영향을 주는 것으로 확인되었다.

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
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    • 제29권4호
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    • pp.427-434
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    • 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.

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

  • 정면우;임화경;전용준;김혜정;박인숙;오우용;왕소영;박윤주;강주희
    • 약학회지
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    • 제46권4호
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    • pp.276-282
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    • 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
    • 한국축산식품학회지
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    • 제36권1호
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    • pp.37-43
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    • 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.

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

  • 김철곤;황지훈;서형준;모진용;정두한;홍석무
    • 대한기계학회논문집A
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    • 제39권4호
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    • pp.423-428
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    • 2015
  • 에어컨 실내기 조립 시 부품간 간섭이 발생하는 위치와 원인 분석을 위해, 3차원 공차해석을 수행하고 부품공차 및 조립 갭을 최적화했다. 민감도 분석을 통해 초기 설계에서 drain과 body 조립부의 불량발생 확률이 72.6%로 가장 높은 것을 확인했고, 또한 유한요소해석(FEA)을 활용 에어컨 실내기의 난방작동 시 열 변형으로 인해 최대 약 1mm의 변위가 발생하여 부품간 간섭이 발생할 수 있음을 확인했다. 이런 부품간 간섭을 최소화기 위해서 3D 공차 해석의 민감도 분석결과를 토대로 drain의 부품공차를 수정하였다. 개선 공차 반영 해석결과 불량률이 0.03%로 크게 감소함을 확인하였다. 또한, 개선공차 반영 시 에어컨 작동 중 열 변형이 발생하여도 부품간 간섭이 발생하지 않음을 FEA를 통해 검증하였다.

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

  • 강창호;김용경;한설화;정율아;박혜민;백남수
    • Journal of Dairy Science and Biotechnology
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    • 제37권1호
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    • pp.40-48
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    • 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.