• 제목/요약/키워드: M71

검색결과 3,323건 처리시간 0.029초

구상성단 M71의 BV CCD 측광: 거리 그리고 나이 (BV CCD PHOTOMETRY OF M71: DISTANCE AND AGE)

  • 임홍서;천문석;변용익;손영종
    • Journal of Astronomy and Space Sciences
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    • 제21권1호
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    • pp.1-10
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    • 2004
  • 이 논문에서는 우리 은하 구상 성단 M7l에 대한 B, V CCD 영상 관측 자료로부터 색-등급도(color-magnitude diagram)를 구하고, 이로부터 이 성단의 거리와 상대적 나이를 결정하였다. M7l의 적색화 현상(E(B - V) = 0.28)과 금속함량(-0.79 < 〔Fe/H〕 < -0.70)은 최근 논문의 값을 채택하였다 이 자료를 토대로 관측으로부터 얻은 M71 색등급도의 기준선을 Hipparcos준왜성의 측광 특성과 비교하여 M71의 거리지수를 (m- M)v = 13.46(${\pm}0.17$)과 같이 결정하였다. 비슷한 금속 함량을 가지는 구상 성단47 Tuc의 색등급도를 이 연구에서 구한M71의 색등급도와 비교한 결과 두 성단의 나이는 상당한 차이가 있음을 확인할 수 있었고, isochrone과의 비교 결과 적어도 20억년 이상의 차이가 존재한다는 사실을 알 수 있었다.

Alkaline Protease 고 생산성 세균의 선별 및 효소 특성 (Screening of Bacillus sp. No. M-71 with High Alkaline Protease Productivity and Some Properties of the Enzyme)

  • 오성훈;오평수
    • 한국미생물·생명공학회지
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    • 제19권1호
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    • pp.1-7
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    • 1991
  • A bacterial strain No.71, which produced alkaline protease, was isolated from soil and identified to the genus Bacillus. With the successive mutation, a mutant strain No. M-71, having high alkaline protease productivity, was obtanined from the parental strain No 71. Alkaline protease productivity of mutant strain No. M-71 was about 50 times as much as that of the parental strain No.71. The enzyme preparations showed strong activities toward casein, the optimum pH being 11.0 and the optimum temperature about $55^{\circ}C$.

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Saccharomyces cerevisiae D-71과 Zygosaccharomyces rouxii SR-S로부터 조제한 원형질체의 안정성 (Stability of Spheroplasts from Saccharomyces cerevisiae D-71 and Zygosaccharomyces rouxii SR-S)

  • 정창기;김찬조;이종수
    • 한국미생물·생명공학회지
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    • 제16권4호
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    • pp.293-296
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    • 1988
  • 고온발효성인 Sacch. cerevisiae D-71과 내삼투압 성인 Zygosacch. rouxii SR-S의 원형질체를 조제하고 분리하여 그의 안정성을 검토하였다. Sacch. cerevisiae D-71의 원형질체는 0.8M KCI 과 1.0M sorbitol에서, Zygosacch. rouxii SR-S의 원형질체는 0.4M KCI과 mannitol에서 가장 안정하였고 두 효모의 원형질체들을 20Kc로 60초간 초음파 처리하였을 때 90% 이상이 파괴되었다. 또한 10000$\times$g로 10분간 처리하였을 때 Sacch. cerevisiae D-71의 원형질체는 93%, Zygosacch. rouxii SR-S의 원형질체는 84%의 안정성을 보였고 이들 원형질체들을 15W의 자외선 등으로 20cm에서 60분간 처리하였을 때 Sacch. cerevisiae의 원형질체는 99%, Zygosacch. rouxii SR-S의 원형질체는 55%가 파괴되었다.

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NEAR-INFRARED PHOTOMETRY OF METAL RICH GLOBULAR CLUSTER M71

  • 경재만;변용익;천문석
    • Journal of Astronomy and Space Sciences
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    • 제14권2호
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    • pp.194-201
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    • 1997
  • We have carried out JK near-infrared photometry for the central region of the metal rich globular cluster M71, whose (K, J - K) color-magnitude diagram is presented here. Using two independent methods we derive the distance modulus to M71, 12.89 and 12.86 $pm0.12$ respectively. The former is derived using the HB luminosity $M_{Ko}$(HB) = -1.15 for globular clusters having metallicity between -1.0 to -0.3 (Kuchinski et al. 1995). The latter is derived through a comparison with IR photometry of stars in the similar metallicity cluster 47 Tuc. We also estimate the reddening to M71, E(J - K) = 0.13, based on E(B - V) = 0.04 of 47 Tuc.

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특성길이 변화에 따른 200 N급 기체메탄-액체산소 소형로켓엔진의 성능 비교 분석 (A Comparative Analysis for the Performance of 200 N-class Gaseous Methane-Liquid Oxygen Small Rocket Engine According to the Characteristic Length Variation)

  • 강윤형;안현종;김정수
    • 한국추진공학회지
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    • 제24권6호
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    • pp.85-92
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    • 2020
  • 200 N급 기체메탄-액체산소 소형로켓엔진의 연소실 특성길이 1.37 m, 1.71 m, 2.06 m에 대한 연소성능 분석을 위해 지상연소시험을 수행하였다. 로켓엔진의 주요 성능 변수로 정상상태에서의 추력, 비추력, 특성속도 등을 획득하였으며, 연소시험을 통해 확인한 성능특성을 CEA 해석으로부터 구한 이론성능과 비교 및 분석하였다. 연소성능에 대한 특성길이의 영향을 관찰한 결과, 최적의 특성길이는 1.71 m와 2.06 m사이에 존재하는 것이 확인되었다.

Inhibitory Effect on Replication of Enterovirus 71 of Herb Methanol Extract

  • Choi, Hwa-Jung;Song, Jae-Hyoung;Ahn, Young-Joon;Kwon, Dur-Han
    • Journal of Applied Biological Chemistry
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    • 제51권3호
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    • pp.123-127
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    • 2008
  • Anti-enterovirus 71 (EV 71) activities of fifteen herb plant species extracts were examined by SRB assay, among which Origanum vulgare and Rosmarinus officinalis (Anna Rosemary) extracts exhibited the activities with $IC_{50}$ of 8.28 and $8.17\;{\mu}g/mL$, respectively. Their 50% cytotoxicity concentrations ($CC_{50}$) were 691.89 and $1104.19\;{\mu}g/mL$, and the therapeutic indices were 83.56 and 135.15, respectively. Amantadine (positive control) showed anti-EV 71 activity with 50% inhibitory concentration and $CC_{50}$ of 4.46 and $145.22\;{\mu}g/mL$, respectively. Addition of the methanol extracts of O. vulgare and R. officinalis (Anna Rosemary) in EV 71-infected Vero cells strongly inhibited the formation of visible cytopathic effects without changing the normal morphology of the cells. These results indicate that methanol extracts of O. vulgare and R. officinalis (Anna Rosemary) may contain antiviral compound inhibiting the EV 71 replication.

CN AND CH BAND STRENGTH VARIATIONS IN M71 GIANTS

  • LEE SANG-GAK
    • 천문학회지
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    • 제38권2호
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    • pp.23-31
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    • 2005
  • CN and CH band strengths for fourteen bright giants in the globular cluster M71 have been measured from archival spectra obtained with the Multiple Mirror Telescope. Adding the collected. data from the literature we confirm a bimodality of CN distribution on the red giant branch and the honzontal branch, and CN-CH anti-correlations on the lower giant branch and horizontal branch. However a CN-CH anti-correlation on the upper red giant branch is not quite clear as those of other branches. The small number If statistics could not be excluded as a possible cause. To confirm this, a greater number of sample stars are needed. We also confirm that the ratio of CN-strong to CN-weak stars is quite different from that in 47 Tuc, although the anti-correlation between CN and CH bands, the bimodality of the CN distribution, and the spatial distribution of CN stars in M71 are found to be similar to those III 47 Tuc.

Saccharomyces cerevisiae D-71과 Zygosaccharomyces rouxii SR-S의 원형질체 형성과 융합 (Protoplast Formation and Fusion between Saccharomyces cerevisiae D-71 and Zygosaccharomyces rouxii SR-S)

  • 이종수;김찬조
    • 한국미생물·생명공학회지
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    • 제16권2호
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    • pp.142-149
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    • 1988
  • 고온에서 고농도 기질을 발효할 수 있는 효모를 육성하고자 8%의 NaCl 내성을 갖은 고온발효성인 Saccharomyces cerevisiae D-71 과 Ca-pantothenate 를 절대요구하는 내삼투압성인 Zygosaccharomyces rouxii SR-S를 친주로 하여 원형질체 형성과 융합조건을 검토하였다. Sacch. cerevisiae D-71은 YEPG 배지에 12시간 배양한 세포를 0.1mM EDTA와 0.5M sorbitol를 함유한 인산완충액(pH7.5)에 현탁시켜 1%의 2-mercaptoethanol로 10분간 전처리한 후 Zymolyase-20T 4.0mg/$m\ell$를 가하여 3$0^{\circ}C$에서 50분간 반응시켰을 때 96% 이상의 수율로 윈형질체가 형성되었고 Zygosacch. rouxii SR-S는 YEMEPG 배지에 24시간 배양한 세포를 0.1mM EDTA와 0.5~l.0M mannitol을 함유한 인산완충액(pH7.0)에 현탁시켜 1%의 2-mercaptoethanol로 10분간 전처리 한 후 Zymolyase-20T 4.0mg/$m\ell$를 가하여 3$0^{\circ}C$에서 120분간 반응시켰을 때 95% 정도의 수율로 원형질체가 형성되었다. 시험효모의 원형질체를 CaCl$_2$와 Sorbitol 및 40% 의 PEG 4000을 함유한 융합배지에 1 : 1로 혼합한 후 35$^{\circ}C$에서 20분간 처리하여 융합시킨 다음 3%의 한천을 함유한 최소배지에 중층하여 5일간 배양하였을 때 9.1$\times$$10^{-6}$의 융합빈도수를 보였다. 또한 주사형전자현미경으로 구형의 원형질체와 융합재생된 타원형의 세포를 관찰할 수 있었다.

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생쥐에 있어서 에탄올의 면역독성에 미치는 메치오닌 식이의 영향 (Effects of Methionine Diets on the Immunotoxicity of Ethanol in ICR Mice)

  • 안영근;김정훈;구기범;문재규
    • 약학회지
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    • 제36권4호
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    • pp.303-314
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    • 1992
  • Experiments were performed on mice to investigate the effect of methionine diets (MET) on the immunotoxicity of ethanol. ICR female mice were divided into 5 groups, Met (Basal (B)+0.19% methionine(M), B+1.71% M and B+5.13%W) and ethanol(4%) were administered ad libitum for 21 days. The mice were evaluated for changes in immune status as measured by antibody titer, Arthus reaction, delayed type hypersensitivity (DTH), rosette forming cell(RFC) and plaque forming cell (PFC) to sheep red blood cells (S-RBC). To investigate the change of the non-specific immune response, the number of leukocytes in peripheral blood and phagocyte activity were measured. The results were summarized as follows: (1) The weight ratios of spleen and thymus to body weight were significantly increased by the B+0.19% M, B+0.57% M and B+1.71% M groups in comparison with control group(B), but B+5.13% M group was significantly decreased. (2) Humoral immune responses were significantly increased by the B+0.19% M and B+0.57% M groups in comparison with control group, but B+5.13% M group was significantly decreased. (3) Cellular immune responses were significantly decreased by the B+1.71% M and B+5.13% M groups in comparison with control group. (4) Phagocyte activities were significantly increased by the B+0.19% M, B+0.57% M and B+1.71% M groups in comparison with control groups, but B+5.13% M group was significantly decreased. (5) The number of circulating leukocyte was significantly increased in the B+0.19% M and B+0.57% M groups in comparison with control group, but B+5.13% M group was significantly decreased.

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