• 한국연초학회지
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• 제11권2호
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• pp.197-202
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• 1989

This experiment was conducted to investigate the effect of growth medium in pots composed of upland soil(S), rice straw manure(M), carbonated rice hull(CRH), and their mixture on growth of tobacco cv. NC 82. The growth of shoot and root was vigorous in order of medium S+M+CRH>M>CRH>S. In M+S medium, root growth in the part of manure was superior to upland soil. But root growth of upland soil part in M+S plot was more vigorous than that in upland soil only. It is possibly due to be influenced by manure in M+S plot. Total length and weight of root, number of roots, and especially for development of adventitious root were closely related to shoot growth. Roots grown in upland soil part was brownish gray in color, while the roots in manure part was milky white. The milky white colored roots had longer life than others. It was concluded that root zone environments derived from several media in pots closely related to shoot growth and disease tolerance of tobacco plant.

• 한국조경학회지
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• 제28권4호
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• pp.1-8
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• 2000

This study is conducted to evaluate the effects of root restriction on growth of maple(Acer palmatum Thumb.). Tow types of container such as clay pot(CP), root control bag(RCB) were used to restrict maple's root and each type of container was divided into 5 sizes. The containers with plants were buried just below the soil level and maples planted directly in the soil (nonrestricted root treatment) were included as comparison. Data were collected on dry weight of leaf, trunk, thick root, rootlet and soil water potential. We have analyzed, simple linear regression, Pearson's Correlation analysis, Duncan's multiple rang test, and Covariance Analysis using SAS statistical software. The results of analysis based on these data are as follows; 1. Total dry weight of maple in CP was significantly larger than in RCB. 2. Difference in growth reduction by the kinds of containers was induced by different hydraulic diffusion ratios between container and soil. Difference in growth reduction by the size of container was induced by the difference density of rootlet and soil moisture contents in the container. 4. Commercial products of root control of root control bag appeared not proper for countries in which fluctuation of rainfall is severe. Because maples in RCB were restricted by excess soil water in the rainy season, or by lack of soil water in the dray season.

• Journal of Ecology and Environment
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• 제42권4호
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• pp.155-162
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• 2018

Background: In ecosystem carbon cycle studies, distinguishing between $CO_2$ emitted by roots and by microbes remains very difficult because it is mixed before being released into the atmosphere. Currently, no method for quantifying root and microbial respiration is effective. Therefore, this study investigated the relationship between soil respiration and underground root biomass at varying distances from the tree and tested possibilities for measuring root and microbial respiration. Methods: Soil respiration was measured by the closed chamber method, in which acrylic collars were placed at regular intervals from the tree base. Measurements were made irregularly during one season, including high temperatures in summer and low temperatures in autumn; the soil's temperature and moisture content were also collected. After measurements, roots of each plot were collected, and their dry matter biomass measured to analyze relationships between root biomass and soil respiration. Results: Apart from root biomass, which affects soil's temperature and moisture, no other factors affecting soil respiration showed significant differences between measuring points. At each point, soil respiration showed clear seasonal variations and high exponential correlation with increasing soil temperatures. The root biomass decreased exponentially with increasing distance from the tree. The rate of soil respiration was also highly correlated exponentially with root biomass. Based on these results, the average rate of root respiration in the soil was estimated to be 34.4% (26.6~43.1%). Conclusions: In this study, attempts were made to differentiate the root respiration rate by analyzing the distribution of root biomass and resulting changes in soil respiration. As distance from the tree increased, root biomass and soil respiration values were shown to strongly decrease exponentially. Root biomass increased logarithmically with increases in soil respiration. In addition, soil respiration and underground root biomass were logarithmically related; the calculated root-breathing rate was around 44%. This study method is applicable for determining root and microbial respiration in forest ecosystem carbon cycle research. However, more data should be collected on the distribution of root biomass and the correlated soil respiration.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.190-199
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• 1991

The purpose of this study was to evaluate the antimicrobial effect of root canal cements such as AH-26, Sealapex, Canals and Apatite root sealers(Type I, II, III) and to determine the efficacy of their activities. S.mutans(AHT), S.sanguis(NCTC 9811) and B.gingivalis(381) were streaked on blood agar and the PVC tybes filled with root canal cements were applied on. Then the microorganisms were cultured for 48 hours, anaerobically. B.cereus(KCTC 1012) was streaked on nutrient agar, PVC tubes were applied on and were cultured for 48 hours, aerobically. The inhibition zones of root canal cements were measured with vernier caliper. The data statistically analyzed, and the results were as followed. 1. Apatite root sealers(Type I, II, III) showed no inhibition zones. 2. AH-26, Sealapex and Canals had inhibition zones with varying degrees. The inhibition zone of AH-26 was greatest and followed by Canals and Sealapex(P<0.01). 3. As time goes by after mixing the root canal cements, AH-26, Canals and Sealapex showed significantly reducing inhibition zones(P<0.01). 4. There were the least inhibition zones of all the root canal cements on S.mutans and followed in such order as; B.gingivalis, S.sanguis and B.cereus(P<0.01).

• 한국작물학회지
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• 제43권1호
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• pp.38-43
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• 1998

This study examined root growth and distribution under the direct seeding of rice cultivars developed in Korea, Japan, and the U.S. Cultivars from the U.S., especially 'M202' and 'Caloro', had a high ratio of the dry matter partitioning for root and top plant components. Caloro had high root and top growth. 'Koshihikari' from Japan showed the lowest ratio of R/T (root/total dry matter) due to the small amount of root and top plant growth. Most Japanese cultivars except transplanted 'Hatsuboshi' showed low ratio of R/T. Patterns of root distribution for each soil block were recorded by the root box-pin board method. Roots of all cultivars were distributed in blocks A, C, and E in the middle of box, i.e., just below the plant base. Roots of 'Dongjin', M202, and Caloro were distributed deeper than the others. Roots of transplanted Hatsuboshi developed much better than direct seeded Hatsuboshi. Total root weight density was highest in Caloro followed by Dongjin, 'Gancheok', 'Calrose', and the others. The root density of Caloro was twice as much as those of the others except Dongjin. According to cumulative percentages of root distribution on each soil layer, roots of most cultivars were distributed below 20cm. The U.S. cultivars showed vertically well developed root systems as compared to others. A large amount of roots were distributed in the top 15cm of soil layer for Hatsuboshi and Koshinikari, and their root systems appeared to be shallow. In contrast, the rates of root distribution in the top 10cm of soil layer were low for Dongjin, Calrose, and Caloro. These cultivars had relatively deep root systems.

• 한국통신학회논문지
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• 제38A권9호
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• pp.759-764
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• 2013

$q{\equiv}5$ (mod 8)의 경우에 유한체 $F_q$상에서 Atkin의 제곱근 알고리즘과 $q{\equiv}9$ (mod 16)의 경우에 Kong의 알고리즘으로부터 일반적인 제곱근 알고리즘을 제안한다. 우리의 알고리즘은 s가 $2^s|q-1$을 만족하는 가장 큰 양의 정수라 할 때, $2^s$차 원시근 ${\xi}$를 미리 계산하였고 s의 값이 작을 때 적용가능하다. 제시한 알고리즘은 제곱근을 계산하기 위해 한 번의 지수계산이 필요하고, Akin, M$\ddot{u}$ller, Kong의 알고리즘과 비교해보아도 유리하다.

• 한국식물병리학회지
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• 제10권3호
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• pp.240-244
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• 1994

Watermelon plants grafted with the root-stock of wild-cucumber (Sicyos angulatus) were not infected by Fusarium oxysporum f.sp. niveum in pot inoculation and infected fields tests. Controlling efficacy of the root-stock grafting with S. angulatus on Fusarium wilt of watermelon was more excellent than that of the root-stock grafting with Lagenaria siceraria. The isolates of Fusarium oxysprum from cucurbitaceae plants had a certain host-specific pathogenicity, but they did not express the absolute one forma specialis-one host-plant phenomenon by the root dipping inoculation. The pathogenic isolates of Fusarium oxysproum from cucurbitaceae crops did not infect the root-stock plant such as S. angulatus, L. siceraria and Cucurbita ficifolia. The fast-wilting of watermelon caused by uncertain agents was observed in watermelon plant grafted with L. siceraria in the continuously cropping fields, but it was not observed in watermelon plants grafted with S. angulatus in the same fields.

• KSBB Journal
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• 제6권1호
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• pp.27-33
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• 1991

감자(Solannum tuberosum) 괴경에 A. rhizogenes를 접종하여 암소에서 배양한 결과 2-4주 후에 hairy root가 유도되었다. 유도된 hairy root는 opine 분석을 통해 agropine과 manopine이 검출되어 형질이 전환되었음을 확인하였으며, 발생이 진행됨에 따라 단백질은 전차 감소 되었고, 전분은 점차 증가함을 보였으며, GS.II의 활성 또한 발생단계에 따라 증가함을 보였다. $Ca^{2+}$ channel blocker 인 verapamil 처리구에서는 약 60% 정도 GS II의 활성이 감소 되었으며, calmodulin inhibitor인 chloropromazine 처리구에서는 GS II의 활성에 별 영향을 미치지 않았다. 한편 peroxidase 활성은 3주 동안 배양한 callus에서 가장 높았으며, peroxidase 양상은 hairy root에서는 pI 5.4, 5.9의 band가 나타난 반면, 3주 동안 배양한 callus에서는 pI 6.4, 7.1, 7.4의 새롱룬 band를 얻었다.

• 한국식품영양과학회지
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• 제39권2호
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• pp.287-293
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• 2010

소맥분에 백합 구근분말을 첨가한 물리적 특성은 백합 구근분말 첨가 비율이 증가할수록 farinogram에서 탄력도는 증가하는 경향이었으나, 점탄성, 흡수율, 흡수 시간 및 안정도는 3%이상 첨가 시 증가 후 감소하는 경향을 보였다. Rapid viscoanalyzer(RVA)에서 유지 강도, 최종점도, breakdown, setback 값, alveogram의 $P_{max}$값과 falling number 값은 감소하였다. 소맥분에 백합 구근의 첨가량과 입도 차에 의한 호화도 특성에서 초기 호화온도는 일반 분쇄 및 미분쇄($10\;{\mu}m$) 백합 구근분말의 종류와 양에 관계없이 영향을 미치지 않았다. Rheofermentometer로 측정한 gaseous release는 전체 $CO_2$ 가스 발생량과 보유량이 감소하였다. 기호도 검사에서는 백합 구근분말의 입도와 첨가 비율에 따른 식빵의 가공적성에서 식감, 향미, 맛에서 유의적인 차이가 나타났으며, 촉감과 크럼 색상은 유의적인 차이가 없는 것으로 나타났다. 한편 식빵의 가공 적성에서 일반 분쇄 3%와 초미분쇄 3% 첨가군이 양호하였으나, 종합적인 평가에서는 대조구 다음으로 미분쇄 백합 구근분말 3% 첨가군에서 우수하였다. 이미 백합 구근의 항산화 활성 등 생리활성은 검증되어져 발표되어 있는 만큼 제빵 가공에서 조직감의 문제를 보완하고 개선한다면 건강 기능성 제빵으로 상품화 가치가 있다고 생각된다.

• 대한소아치과학회지
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• 제39권4호
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• pp.366-372
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• 2012

본 연구의 목적은 현재 많이 사용되고 있는 ProRoot MTA (Dentsply Tulsa, USA)와 최근 국내에서 새로 개발된 OrthoMTA (Bio MTA, Korea)의 감염된 근관에서 주로 발견되는 3개의 미생물에 대한 효과를 다양한 농도와 시간에서 비교하는 것이다. 50, 25, 12.5 mg/mL의 농도로 준비된 ProRoot MTA와 OrthoMTA에 Enterococcus faecalis, Fusobacterium nucleatum 그리고 Staphylococcus epidermidis를 접종 후 24, 48, 72시간에 항미생물 효과를 관찰하여 다음과 같은 연구결과를 얻었다. E. faecalis의 경우 ProRoot MTA와 OrthoMTA 50, 25, 12.5 mg/mL 농도의 모든 시간대에서 세균을 완전히 억제하지는 못했지만 양성 대조군에 비해 성장이 조금 감소한 양상을 보였다(p < 0.05). F. nucleatum의 경우 ProRoot MTA 50 mg/mL 농도의 24시간에서 미생물을 억제하였으나 시간이 지남에 따라 세균의 성장을 보인 반면 OrthoMTA의 경우 같은 농도에서 시간이 지나도 계속 세균을 억제하였다(p < 0.05). S. epidermidis의 경우 ProRoot MTA 50 mg/mL, OrthoMTA 50, 25 mg/mL 농도의 24시간에서 억제 효과를 보였으나 시간이 지나면서 세균이 조금씩 성장하였다. 그러나 전체적으로 모든 농도와 시간에서 양성 대조군에 비해서는 억제 효과를 나타냈다(p < 0.05). 본 연구를 통해 국내에서 새로 개발된 OrthoMTA는 기존의 ProRoot MTA보다 항균활성을 가지고 있음을 알 수 있었다.