• Title/Summary/Keyword: reversion

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Studies on the mechanisms of suppression in Aspergillus nidulans (Aspergillus nidulans의 역제의 유전자의 작용기작에 관한 연구 II)

  • 문은표;강현삼
    • Korean Journal of Microbiology
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    • v.20 no.1
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    • pp.1-10
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    • 1982
  • From Aspergillus nidulans, six suppressor mutants, MSI-MS6, were isolated, and their characteristics were analysed. These were the suppressor mutants for acriflavin resistant and nicotinamide auxotrophic mutant phenotypes. MS1, MS2, MS5 and MS6, were linked to the chromosome IV, I, II respectively, and MS2 was linked to one of the rest chromosomes, MS3 and MS6 mutants had both suppressors for acriflavin resistant marker and for nicotinamide auxotrophic marker. In order to know the stability and efficiency of the suppressors, their reversion frequencies, that is, frequencies of losing the suppressibility, were analysed. Only MS3 and MS5 were reversed with high frequency. The four mutants didn't lose their suppressibilities, and this meant that the suppressors of these four were very stable and highly effcient. The suppressor specificities of these mutants were tested for other mutant's phenotype marker. One of the six suppressors, MS1, had the suppressor specificity for acriflavin resistant marker of 163 strain.

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A Study on the Ambiguity of the Boundary in the Architectural Interior and Exterior Space (건축 내$\cdot$외부공간 경계의 모호성에 관한 연구)

  • Kwak Ki-Pyo
    • Korean Institute of Interior Design Journal
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    • v.14 no.2 s.49
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    • pp.20-28
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    • 2005
  • This paper investigates that the ambiguity of the boundary between interior space and exterior space in architecture appears universally in history and reveals the various aspects of ambiguous boundary in architecture. The space is formed by the relationship with the surroundings and the boundary of two opposite spaces is apt to be ambiguous according to lots of complex factors. Before Modern Architecture the boundary of interior and exterior space had a tendency to be ambiguous by modifying compositional method of material boundary, that is semi interior-exterior space, the reversion of interior and exterior space and space in space. After Modern Architecture the meaning of physical boundary in space is lost along with dissolution of boundary over the society and the boundary of space comes to be dematerialized by the technology and the change of space perception. The phenomenon of deconstruction in spacial boundary accelerate increasingly according to fluid space, mutually interpenetrated space, visual transparency and adjustment of layers. And contemporary technology is collapsing the meaning itself of space division fundamentally.

A Study on the Interrelationship between Otto Wagner and Gustav Mahler in Belle Epoque (벨 에포크의 오토 바그너와 구스타프 말러의 상관성에 관한 연구)

  • Lee Hong-Kyu;Park Joung-Lan;Dong Jung-Keun
    • Korean Institute of Interior Design Journal
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    • v.14 no.2 s.49
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    • pp.29-36
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    • 2005
  • There have been a little attempts to draw analogy between architecture and music. There are many objective and subjective factors for this to be true. If, however, the two arts are out of much the same social conditions, they show a degree of conformity in design and general organization. Our study shows the interrelationship between Otto Wagner and Gustav Mahler in Belle Epoque. In order to clarify the interrelationship between architecture and music, this study examines works of Otto Wagner on the basis of the characteristic of Gustav Mahler. This comparison between Otto Wagner and Gustav Mahler follows : in Belle Epoque, they have the same tendency to 1) the disintegration of historicism, 2) the style of description, 3) the reversion, 4) the giganticness, 5) the change of materials and 6) the proportion.

A Study on Pairs Trading Performance in Global Futures Markets (페어트레이딩 전략의 수익성 연구 : 해외 선물시장을 중심으로)

  • Kim, Beomsu;Choi, Heung Sik;Kim, Sunwoong
    • Korean Management Science Review
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    • v.33 no.4
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    • pp.1-15
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    • 2016
  • Pairs trading is an arbitrage trading strategy using statistical properties of the spreads between two assets. This study analyzes the performance of the statistical pairs trading with the pairs selected from the same category as well as from the different category in the CME and other futures markets. Empirical results show that the pairs trading performance of the same category is poor whereas that of the different category proves profitable. This implies that the spreads between different category pairs can have the mean reversion property if pairs are properly selected using co-integration test, which is contrary to the existing research results on the overseas futures pairs trading.

Mutagenicity of 2-[(4- Cyanophenyl)amino] -3-chloro-1, 4- naphthalenedione (NQ-Y15) (2-[(4- Cyanophenyl)amino] -3-chloro-1, 4- naphthalenedione (NQ-Y15)의 돌연 변이원성)

  • 김봉희;정기화;유충규;창동신;이기선;전선덕;소동수;채상호;문창규
    • Environmental Analysis Health and Toxicology
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    • v.15 no.4
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    • pp.157-163
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    • 2000
  • 2- [(4- Cyanophenyl)amino] -3-chloro-1, 4- naphthalenedione (NQ-Y15) was asssayed for its genotoxic potential by using Salmonella typhimurium reversion assay and in vitro chromosome aberration test on Chinese hamster lung cells. In the Ames test, NQ-Y15 induced his + revertants of Salmonella typhimurium TA 98 and TA1537, reaching levels twice the negative control values. But, NQ-Y15 induced only his+ revertants of Salmonella typhimurium TA1537 more than twice the control values under the condition with metabolic activation system. In the cytogenetic test on chinese hamster lung cells. NQ -Y15 showed significant chromosomal aberrations, but the incidence was significantly reduced in the presence of metabolic activation.

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Effects of K or Ca Supplement on Glucose Tolerance and Insulin Response in Subjects with Furosemide Diuresis (Furosemide 이뇨중의 내당능 및 Insulin 반응에 미치는 K 또는 Ca 보충투여의 영향)

  • Sung, Ho-Kyung;Koh, Joo-Hwan;Ryu, Yong-Woon
    • The Korean Journal of Physiology
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    • v.10 no.2
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    • pp.29-37
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    • 1976
  • Effect of furosemide administration on glucose tolerance, insulin-and HGH response following parenteral glucose loading was studied in healthy subjects. Effects of potassium or calcium on the furosemide induced changes were also observed in the same subjects. Furosemide administration resulted in a considerable reduction in the magnitude and duration of insulin response although no obvious changes were observed in glucose disappearance from the circulation. Oral potassium or calcium supplement to the furosemide treated subjects showed a reversion toward normal of the insulin response. The author suggested that a decreased endogenous insulin production resulting from the potassium and/or calcium depletion is responsible for the changes observed. In those subjects who receive parenteral nutrition if administration of furosemide is essential, it should be supplemented by potassium and/or calcium.

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Genotoxicological Safety of the Gamma-Irradiated Korean Red Ginseng In vitro (감마선 조사 홍삼의 안전성에 관한 유전독성학적 연구)

  • 조성기;육홍선;변명우
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.3
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    • pp.491-496
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    • 1996
  • This experiment was performed to determine the safety of the Korean red ginseng irradiated with gamma rays with respect to genotoxicity. Ethanol extracts of the 5 and 10 kGy gamma-irradiated red ginseng were examined in two short-term in vitro tests : (1) Salmonella typhimurium reversion assay(Ames test) in strain TA 98, TA 100 and TA 102 (2) Micronucleus test in cultured Chinese hamster ovary(CHO) cells. No mutagenicity was detected in the two assays with or without metabolic activation. It was suggested that the Korean red ginseng irradiated with gamma rays did not cause genotoxicity in vitro. Further tests of genotoxicity in vivo, chronic and reproductive toxicity should be carried out to determine whether it is safe to irradiate Korean red ginseng with practical doses of gamma rays.

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Weldability of Al Alloys, Part II :HAZ Cgaracteristics (알루미늄 합금의 용접특성 - part II)

  • 이창희;장래웅
    • Journal of Welding and Joining
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    • v.11 no.1
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    • pp.2-8
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    • 1993
  • A literature review was conducted to gather informations available on the welding metallurgy of aluminum alloys, emphasized on characteristics in the heat affected zone(HAZ). Nominal metallurgical reactions that occur in aluminum alloys provide a basis for understanding aluminum welding metallurgy. However, welding reactions differ to some extent because of the relatively short times involved, and the non-isothermal heating excursed. For non-heat treatable alloys, welding primarily affects these alloys by annealing (recrystallization and growth) and to a less extent, changes in low temperature precipitates. In the case of heat treatable alloys, the resulting HAZ properties depend upon alloy composition, starting temper, heat input and post weld heat treatments.

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Polymeric Microspheres As Antigen Delivery Systems

  • Oh, Yu-Kyoung
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.11a
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    • pp.115-120
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    • 1996
  • Vaccination has been considered to be the most effective way to control infectious diseases. Currently, many vaccines used in humans are live-attenuated or killed microorganisms. Polio, mumps, and measles vaccines are live-attenuated. Killed vaccines include cholera and pertussis vaccines, These conventional vaccines, however, suffer from some problems. In the case of live-attenuated vaccines, reversion to virulence is observed in a small but significant number of clinical cases each year. In killed vaccines, due to the possible hazard to employees working with live pathogens, the cost of preparation is high. Killed vaccines also need to be given in multiple doses, Furthermore, both live-attenuated and killed vaccines have possible presence of cellular materials leading to side effects. Moreover, there are diseases such as malaria and hepatitis for which conventional attenuated and killed vaccines are not available because the pathogens cannot be grown in sufficient amounts to allow the classical methods to be used.

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The Evaluation of Genotoxicities of Antifungal 6-[(N-Halophenyl)amino]-7- Chlore-5,8-Quinolinediones (항진균성 6-[(N-Halophenyl)amino]-7-Chloro-5, 8-Quinolinedione의 유전독성 평가)

  • 유충규;허문영;박윤미;윤여표
    • Biomolecules & Therapeutics
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    • v.3 no.3
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    • pp.182-187
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    • 1995
  • The clastogenecity and mutagenicity of antifungal 6-[(N-halophenyl)amino]-7-chloro-5, 8-quinolinedione (RCK 3, 7, 13, 14, and 15) had been evaluated. Salmonella typhimurium reversion assay (Ames test) was used to test the mutagenicity of RCKs. RCK14 was mutagenic in S. typhimurium(TA98 and TA100) with and without rat liver microsomal activation. Whereas RCK3, 7, 13 and 15 were negative in Ames test with Salmonella typhimurium(TA98 and TA100), The clastogenecity was tested on the RCKs with in vivo mouse micronucleus assay. All of RCKs tested did not show any clastogenic effect in mouse peripheral blood. Thus RCKs were not supposed to cause any chromosomal damage termed micronuclei. These results indicate that RCK 3, 7, 13 and 15 have no genotoxic potential under these experimental condition.

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