• 제목/요약/키워드: Accumulation period

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Glucanhydrolase from Lipomyces starkeyi KSM 22 as Potential Mouthwash Ingredient

  • Kim, Doman;Ryu, Su-Jin;Son, Eun-Ju;Chung, Hyun-Ju;Kim, Seung-Heuk;Kim, Do-Won;Day, Donal-F.
    • Journal of Microbiology and Biotechnology
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    • v.12 no.6
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    • pp.993-997
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    • 2002
  • A glucanhydrolase (a DXAMase exhibiting both dextranolytic and amylolytic activities) from Lipomyces starkeyi KSM 22 hydrolyzed polysaccharides having ${\alpha}-(1{\rightarrow}3)-,\;{\alpha}(1{\rightarrow}4)-,\;and\;{\alpha}-(1{\rightarrow}6)$-D-glucosidic linkages. The oral hygiene benefits of DXAMase-containing mouthwash were examined in relation to human experimental gingivitis during a 3-week period without brushing. The DXAMase-treated group exhibited a lower increase in plaque accumulation and gingival index score than the chlorhexidine-treated group. The DXAMase-treated group also showed less tongue accumulation, bad taste, and tooth staining, thus indicating a positive role for DXAMase as an antiplaque agent ingredient.

Accumulation and Depuration of Fluoranthene, a Polycyclic Aromatic Hydrocarbon, in Rockfish Sebastes schlegeli (조피볼락 (Sebastes schiegeii)에서 다환성방향족탄화수소 fluoranthene의 축적과 배설)

  • Park Kwan Ha
    • Environmental Analysis Health and Toxicology
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    • v.20 no.3 s.50
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    • pp.223-228
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    • 2005
  • Rockfish Sebastes schlegeli was exposed to fluoranthene, a ubiquitous polycyclic aromatic hydrocarbon, at 1 and 10 $\mu$g/L for 4 weeks followed by depuration period of 8 weeks. Although the fluoranthene in the p]asma reached only 1.8$\~$1.9 times seawater concentration, it was 6.5 $\~$ 15.7 times higher in the liver, spleen and bile indicating efficient accumulation in the lipid -containing body tissues. When the exposed fish were then maintained in clean water, rapid fluoranthene decline occurred in the initial 2 weeks followed by a rather slow phase. This result suggests that fluoranthene accumulates efficiently provided the existence in the culture medium, but the contaminant disappears rapidly once the chemical source is removed. The fluoranthne residue in fish tissues my be a good indifator for relent PAHs exposure.

Canavanine Effects on the Amylase Activity and Protein Content in Barley Half Seeds (Canavanine에 의한 보리 무배부 종자의 Amylase 활성과 단백질 함량의 변화)

  • 전방욱
    • Journal of Plant Biology
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    • v.26 no.4
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    • pp.173-180
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    • 1983
  • L-canavanine was added to GAs treated barley seeds, and induced amylase activity, soluble protein content, and arginine content were mesured. Canavanine, added at the beginning of the incubation period, inhibited amylase activity and protein accumulation. Amylase activity decreased markedly by addition of canavanine at 6 hr after incubation, where soluble protein content was not affected. The addition of canavanine after 12 hr incubation did not show serioud inhibited effect on the amylase activity and protein accumulation. GAs incubation caused decrement in arginine content per mg protein, but it was somewhat recovered by canavanine treatment. The longer the time between GAs and canavanine addition was, the less the recovery ration was. Arginine content in the $\alpha$-amylase fraction (ammonium sulfate 20~50% saturation) was lower than in 0~20% fraction, but higher than in 50~80% fraction. These results and control expreiments, using cordycepin and cycloheximide, support the idea that canavanine might incorporate into protein.

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Moment resisting steel frames under repeated earthquakes

  • Loulelis, D.;Hatzigeorgiou, G.D.;Beskos, D.E.
    • Earthquakes and Structures
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    • v.3 no.3_4
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    • pp.231-248
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    • 2012
  • In this study, a systematic investigation is carried out on the seismic behaviour of plane moment resisting steel frames (MRF) to repeated strong ground motions. Such a sequence of earthquakes results in a significant damage accumulation in a structure because any rehabilitation action between any two successive seismic motions cannot be practically materialised due to lack of time. In this work, thirty-six MRF which have been designed for seismic and vertical loads according to European codes are first subjected to five real seismic sequences which are recorded at the same station, in the same direction and in a short period of time, up to three days. Furthermore, the examined frames are also subjected to sixty artificial seismic sequences. This investigation shows that the sequences of ground motions have a significant effect on the response and, hence, on the design of MRF. Additionally, it is concluded that ductility demands, behaviour factor and seismic damage of the repeated ground motions can be satisfactorily estimated using appropriate combinations of the corresponding demands of single ground motions.

The clinical Rxperiences and Long Term Results with 369 cases of Coronary Artery Bypass Graft Surgery (관상동맥 우회로 조성수술 369례의 임상성적 및 장기결과)

  • 유경종
    • Journal of Chest Surgery
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    • v.28 no.6
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    • pp.583-590
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    • 1995
  • The three hundred and sixty nine patients who underwent either isolated or concomitant coronary artery bypass graft surgery since May, 1977 till December, 1993 at the Yonsei University Cardiovascular center were studied with respects to the incidence of operative risk factors, surgical methodology and consequent results. The patients were classified into two periods, according to the time of the surgery in relation to the date of the opening of the Yonsei cardiovascular center. Period I[1977 to 1990 , consisting of the patients who underwent surgery prior to the opening date, harboured a total of 189 patients with the mean age of 55 years, and the second, Period II[1991 to 1993 , those who underwent after the opening, of 180 patients with the mean age of 60 years. The Period II patients were involved in more operative risk factors, compared to the ones in Period I. The anatomy of the coronary arteries of the patients of Period II were more likely to have multilesional and left main disease. The patients in Period I were older, had more prominent left ventricular dysfunction and were more likely to be exposed to the risk factors. The number of implanted grafts were greater period II[average of 2.5 grafts per patient in Period I VS 3.2 in Period II and the frequency which the used left internal mammary artery was also significantly higher in Period II[49 and 104 cases in Period I and Period II . The incidence of perioperative myocardial infarction was 20 patients[10.6% in Period I, 14 patients[7.8% in period II. And the operative mortality was 20 patients[10.6% in period I, 8 patients[4.4% in period II. In conclusion we think that the operative results have improved in Period II, compared to that of Period I, in spite of the higher risks, due to accumulation of surgical experiences, improved surgical techniques and myocardial protection, specialized teamwork, application of the intraoperative TEE and appropriate pharmacological interventions by anesthesiologist.

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The Effects of the Mixture of Herbal Extract on Developing Plaque and Gingivitis (생약복합제재에 의한 구강양치가 치태 및 치은염에 미치는 영향)

  • Shin, Sug-Rang;Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
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    • v.28 no.2
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    • pp.377-388
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    • 1998
  • This double-blind controlled clinical and microbiological study was carried out to determine the effects of mouthwash preparation containing the mixture of herbal extract on developing plaque and gingivitis in the experimental gingivitis model. Following a 2-week normalization period, 34 dental students were distributed randomly into 1 of 3 treatment groups. They rinsed, under supervision, two times daily for 3 weeks with either normal saline(CT), 0.1% chlorhexidine(CH), or the mixture of herbal extract (HT), but refrained from any oral hygiene measures. The Plaque Index(PlI), the Gingival Index(GI), and the amount of Gingival Crevicular Fluid(GCF) were measured at week 0,1,2, and 3 of the experimental period, while the assessment of total wet weight of plaque and the phase contrast microscopic examination of plaque were performed at the end of experimental period(3 weeks). Subjects using mouthrinse preparation containing the mixture of herbal extract demonstrated negligible, if any, changes in the accumulation and microbial composition of plaque compared to those using normal saline, while the reduction of gingival inflammation by this mixture was highly significant and comparable to that of chlorhexidine. The results of this study indicate that the preparation containing the mixture of herbal extract do not provide any antiplaque benefits but is very effective in inhibiting the development of and in reducing existing experimental gingivitis when used as mouthrinse. Further research is needed to determine whether a significant reduction of gingival inflammation without a concomitant decrease in plaque accumulation is of clinical importance.

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Effects of intermittent effluent recycling on the performance of UASB process (간헐적인 유출수 반송이 UASB 반응조 운전효율에 미치는 영향)

  • 이헌모;양병수
    • Journal of Environmental Science International
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    • v.2 no.4
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    • pp.317-324
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    • 1993
  • Effluent recycling effect on UASB reactor performances is known as an important operational factor. In the present study, the possibility of intermittent recycle in UASB process for saving the power consumption was examined at different organic loading and various operational modes in recycle time period. The organic removal efficiencies of the reactors operated with the intermittent effluent recycle were considerably higher compared to those without the effluent recycle. In the intermittent recycle mode, the organic removal efficiencies slightly decreased as the non-recycle time period in the operational mode increased. Proper ratio of recycle and non-recycle time period in the mode seemed to be required to prevent the produced biogas from accumulation in the sludge bed, which caused dead zone in the reactor and sludge loss when the gas was escaped from the bed at the certain pressure.

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A Study on the Characteristics of Priming Discharge in the PDPs (PDP의 프라이밍 방전특성에 관한 연구)

  • 손현성;채승엽;염정덕
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2002.11a
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    • pp.29-33
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    • 2002
  • Period which does an electric condition of panel in reset in the driving method of PDP is reset period. This research experimentally analyzed the priming discharge characteristic of reset period. The amount of wall charge and the accumulation time accumulated by priming discharge are unrelated to width of priming pulse. And, self-erase discharge has the relation in the amount of wall charge by priming discharge. Then, it relates also to space charge generated by priming discharge. Moreover, space charge which helps self-erase discharge exists to about 22$mutextrm{s}$ after generating priming discharge. And, it is suitable within 12$mutextrm{s}$ of priming pulse width for efficient reset.

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Collection and Analysis of Automotive Field Reliability Data (자동차 필드데이터 수집 및 신뢰도 분석)

  • Kwon, Young-Il
    • Journal of Applied Reliability
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    • v.8 no.1
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    • pp.1-13
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    • 2008
  • A methodology for collection and analysis of automotive field reliability data is presented. Automotive warranty system usually covers a pre-determined period of time and/or mileage accumulation. Therefore mileage information for the vehicles that have not experienced any failure or problems during the warranty period is not available. In this paper, a reliability analysis method using the estimated mileage distribution from an additional survey for vehicles that have not any record during the warranty period is proposed. Methods of reliability analysis using the warranty information collected under the EU and US warranty policies are also provided.

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Effect of Nitrogen Fertilization and Agronomic Stage on Nitrate Accumulation and Forage Yield of Sorghum Sudangrass Hybrid (질소시비수준이 생육단계별 수단그라스계 교잡종의 질산염 축적 및 수량에 미치는 영향)

  • Yoon, C.;Choi, K.C.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.19 no.1
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    • pp.81-88
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    • 1999
  • A field experiment with 200, 400 and $600kg{\cdot}N/ha/year$ application levels was carried out to study the nitrate nitrogen accumulation and forage yield of sorghum sudangrass hybrid(Xtragraze II) at Iksan College Farm in 1995. The nitrate nitrogen contents were increased by the application of nitrogen and decreased as the plant matured, then the accumulation of nitrate nitrogen started from 200kg application, and exceeded the safe level of ruminants at the level of 400kg application during the whole growing period. In the early stage of growth, nitrate nitrogen contents of sorghum sudangrass hybrid were increased by rainfall during the dry season, but these contents are almost kept constantly at the low level in the later stage of growth. Accumulation of nitrate nitrogen in the morning had a greater tendency than that of the afternoon. A sum exceeding $200kg{\cdot}N$ does not necessarily result in increase the amount of nitrate nitrogen in sorghum sudangrass hybrid.

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