• Title/Summary/Keyword: Buffer content

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Planning for Safely Control on Hazardous Material Distribution Depot.

  • Roh, S.K.;Jun, S.W.;Kang, T.H.;Seo, Y.M.
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.260-268
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    • 1997
  • The safety of LPG vessel storage has been simply designed and controled with blast wave barrier structure concept regardless of its quantity or hazardous situation. The limit of regal controls on LPG vessel storage need to be identified in terms of safety buffer distance from LPG explosion. The level of overpressure effect and heat radiation In the safety structure and neighbouring human activity required to be estimated to find the gap between existing controls on such storage. To this content the paper discuss the issues on the approach In the blast wave barrier and safety separation distances.

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Isolation of High-Quality mRNA from Tannin-Rich Persimmon Fruit (고 Tannin 함유 감과실로 부터 mRNA의 분리)

  • ;Dav
    • Food Science and Preservation
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    • v.4 no.1
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    • pp.45-51
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    • 1997
  • In our studies on the role of $\beta$-galactosidase in fruit softening, significant difficulty, was encountered in our attempts to extract RNA from persimmon(Diospyros kaki L. cv. Fuyu) fruit due to astringency and tannin content. Initial, unsuccessful RNA extractions involved methods using guanidinium isothiocyanate/CsCl with and without polyvinylpyrrolidone(PVP), phenol/sodium lauryl sulfate(SDS), guanidinium hydrochloride, as well as polysomal RNA purification method that used 0.2 M Tris-HCI (pH 9.0) containing KCI, Mg-acetate, EDTA, $\beta$-mercaptoethanol, and sucrose. A method was devised which employed treatment of fruit with CO2 gas to diminish astringency prior to RNA extraction, followed by extraction of tissue powders with Proteinase K extraction buffer containing PVP and ascorbate at an alkaline pH. This procedure resulted in the removal of tannins and other polyphenolics and extraction of relatively large amount of high-quality RNA suitable for cDNA library construction and polymerase chain reaction(PCR). Futhermore, the procedure does not use the toxic and corrosive chemical guanidinium isothiocyanate or require ultracentrifugation.

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Studies on the Protoplast Fusion between Lactobacillus casei and Lactobacillus delbrueckii (Lactobacillus casei와 Lactobacillus delbrueckii간의 Protoplast 융합에 관한 연구)

  • 전홍기;김미경;백형석
    • Microbiology and Biotechnology Letters
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    • v.20 no.1
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    • pp.6-13
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    • 1992
  • - Protoplast fusion between lincomycin resistant Lactobacillus casei KCTC 1121 and rifarnpicin resistant Lactobacillus delbrueckii JK-414 was attempted to obtain the improved strains. Protoplasts of L. casei and L. delbrueckii were produced by mutanolysin digestion at $42^{\circ}C$ for 15 min. L. casei cells were converted to protoplasts by treating with 5 $\mu g$ / m l of mutanolysin in 20 mM HEPES buffer (pH 7.0) containing 0.75 M sucrose at the middle logarithmic growth phase. In case of L. delbrueckii 1.0 M sucrose was used osmotic stabilizer. Regeneration of protoplast in both strains was efficiently accomplished on the regeneration medium containing 10% sucrose, 6 mM $MgC1_2, 6 mM CaC1_2$, and 2.5% gelatin. Protoplast fusion between L. casei and L. delbrueckii was carried out in the presence of 40% of PEG 4,000. The frequency of protoplast fusion was found to be about $3.2\times 10^4$. Acid production of L. casei was better than that of L. delbrueckii. Among fusants, F23 and F35 exhibited excellent lactic acid production. F23 and F24 exhibited the improved proteolysis compared to that of the parent strains and they had twice as much as DNA content of the parents.

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A Hybrid Transmission Scheme for Efficient Video Streaming (네트워크 및 버퍼 상태를 모두 고려한 혼합형태의 비디오 스트림 전송기법)

  • Lee, Sun-Hun;Chung, Kwang-Sue
    • Journal of KIISE:Information Networking
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    • v.34 no.4
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    • pp.276-286
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    • 2007
  • Existing streaming mechanisms have no consideration for the characteristics of streaming applications because they only consider network stability. In this paper, in order to overcome limitations of the previous work on video streaming, we propose a new video streaming mechanism called "HAViS(Hybrid Approach for Video Streaming)". The proposed mechanism includes more sophisticated features that consider both network and user requirements. Therefore, the HAViS mechanism improves the network stability by adjusting the sending rate of video stream based on the network state and it also provides the smooth playback by preventing the buffer underflow or overflow. Moreover, it is designed to take into consideration the streaming video content. Through the simulation, we prove that the HAViS mechanism efficiently uses the buffer resources and provides improved network stability and smooth playback.

Dissolution Rate Improvement of Tinidazole Tablets using PEO and HPMC (PEO와 HPMC를 이용한 티니다졸 정제의 용출율 개선)

  • Kim, Kyung-Joo;Park, Jun-Bum;Choi, Jong-Seo;Hwan, Hwang-Chang;Lee, Joeng-Sig;Kang, Chin-Yang
    • Journal of Pharmaceutical Investigation
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    • v.39 no.1
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    • pp.7-12
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    • 2009
  • A novel polymeric tablet of Tinidazole was formulated to treat Helicobacter pylori and Giardia lambria more efficiently, It was possible to reduce hepatotoxicity by controlling the release of Tinidazole after peroral administration. A gastric retentive formulation made of naturally occurring carbohydrate polymers and containing Tinidazole was tested in vitro for swelling and dissolution characteristics. Tinidazole tablets containing various concentration of either PEO or HPMC were prepared by the wet granulation method. In vitro release of Tinidazole at pH 1.2 and pH 6.8 buffer solutions was observed at $37^{\circ}C$ by using a KP dissolution method and an UV (313 nm) spectrophotometer. Compared to a commercial Tinidazole tablet, in vitro release of Tinidazole at both pH 1.2 and pH 6.8 buffer solutions significantly decreased as the concentration of PEO or HPMC in the tablet increased up. And the gastric retentive formulation hydrated and swelled back to about 50% of its original size in 30 min. Thus, it was possible to control the release of Tinidazole by changing the content of PEO or HPMC in the tablet, thereby manipulating the release rate and the retention of Tinidazole.

Change in Nitrogen Fractions and Ruminal Nitrogen Degradability of Orchardgrass Ensiled at Various Moisture Contents and the Subsequent Effects on Nitrogen Utilization by Sheep

  • Nguyen, H.V.;Kawai, M.;Takahashi, J.;Matsuoka, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.9
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    • pp.1267-1272
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    • 2005
  • The effect of various moisture contents of fresh forage on the change in nitrogen (N) fractions, in vitro ruminal N degradability, and the subsequent N utilization of silage in sheep were evaluated. Orchardgrass (Dactylis glomerata L.) with high (HM, 76%), medium (MM, 65%) and low (LM, 40%) moisture contents were ensiled into silos of 120 L capacity for 120 days. A nitrogen balance trial was conducted using a 4${\times}$4 Latin square design consisting of four dietary treatments (i.e. fresh forage, HM, MM and LM silages) and four wethers. With respect to N fractions, fraction 1 (buffer solution soluble N), fraction 2 (buffer solution insoluble N-neutral detergent insoluble N), fraction 3 (neutral detergent insoluble N-acid detergent insoluble N), and fraction 4 (acid detergent insoluble N) were determined. The proportion of fraction 1 in silages tended to decrease, while the in vitro ruminal degradability of insoluble N increased (p<0.05) with lower moisture contents at ensiling. Consequently, nitrogen utilization in sheep tended to improve as the moisture content of ensiled grass was decreased, with a negative correlation (p<0.01) between urinary N and the in vitro ruminal degradability of insoluble N. The averaged N retentions for HM, MM, and LM silage treatments were 59, 73 and 79% of that for fresh forage, respectively.

Separation and Determination of Acteoside in Pedicularis resupinata var. oppositifolia by Ion Pair Liquid Chromatography (이온쌍 액체 크로마토그래피에 의한 마주송이풀 중의 Acteoside의 분리와 정량)

  • Yun, Young Ja;Yu, Gu Yong
    • Analytical Science and Technology
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    • v.8 no.2
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    • pp.161-166
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    • 1995
  • Determination of acteoside in Pedicularis resupinata var. oppositifolia has been studied using ion pair liquid chromatography. Sample was extracted with 40mL methanol for 4 hrs. The extract was cleaned up by using Sep-Pak $C_{18}$ catridge and 8mL aqueous methanol eluent(methanol 50%, water 50%, phosphate buffer pH=8.0). Its determination was performed by means of IP-HPLC with a Hamilton PRP-1 polystyrene-divinylbenzene reversed phase column($15cm{\times}4.6mm$ i. d., $5{\mu}m$) and an aqueous methanol eluent(methanol 60%, water 40% phosphate buffer pH=8.2) containing of $5.0{\times}10^{-3}M$ tetrabutylammonium bromide. The established method was applied to the sample that was collected in area of Pyung Chang gun. As a result, its content ranges showed to be 0.062~0.076%.

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Current Status of the Numerical Models for the Analysis of Coupled Thermal-Hydrological-Mechanical Behavior of the Engineered Barrier System in a High-level Waste Repository (고준위폐기물처분장 공학적방벽시스템의 열-수리-역학적 복합거동 해석 모델 개발 현황)

  • Cho, Won-Jin;Kim, Jin Seop;Lee, Changsoo;Choi, Heui-Joo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.10 no.4
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    • pp.281-294
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    • 2012
  • The current status of the computer codes for the analysis of coupled thermal-hydrological-mechanical behavior occurred in a high-level waste repository was investigated. Based on the reported results on the comparison between the predictions using the computer codes and the experimental data from the in-situ tests, the reliability of the existing computer codes was analyzed. The presented codes simulated considerably well the coupled thermal-hydrological-mechanical behavior in the near-field rock of the repository without buffer, but the predictions for the engineered barrier system of the repository located at saturated hard rock were not satisfactory. To apply the current thermal-hydrological-mechanical models to the assessment of the performance of engineered barrier system, a major improvement on the mathematical models which analyze the distribution of water content and total pressure in the buffer is required.

Enantioselective Determination of Cetirizine in Human Urine by HPLC

  • Choi, Sun-Ok;Lee, Seok-Ho;Kong, Hak-Soo;Kim, Eun-Jung;Parkchoo, Hae-Young
    • Archives of Pharmacal Research
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    • v.23 no.2
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    • pp.178-181
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    • 2000
  • In order to study the simultaneous determination of (+)- and (-)-cetirizine in human urine we have developed a chiral separation method by HPLC. A chiral stationary phase of $\alpha$$_1$-acidglycoprotein, the AGP-CSP was used to separate the enantiomers. The pH of the phosphate buffer, as well as the content of the organic modifier in the mobile phase, markedly affected the chromatographic separation of (+)- and (-)-cetirizine. A mobile phase of 10 m㏖/1 phosphate buffer (pH 7.0)-acetonitrile (95 : 5, v/v) was used for the urine assays. Ultraviolet absorption was monitored at 230nm and roxatidine was employed as the internal standard for quantification. (+)-Cetirizine, (-)-cetirizine and the internal standard were eluted at retention times of 12, 16, and 32 mins, respectively. The detection limit for cetirizine enantiomers was 400 ng/$m\ell$ of urine. A pharmacokinetic study was conducted with the help of 5 healthy female volunteers who were administered with a single oral dose of racemic cetirizine (20 mg). The peak area ratios provided by the cetirizine enantiomers were linear(r>0.997) over a concentration range of 2.5-200 ${\mu}g/ml$. The peak of the excreted cetirizine enantiomers appeared in the urine sample during the period of 1-2 hrs following the administration of the oral dose. The excreted level of (+)-cetirizine was slightly higher than (-)-cetirizine but the difference was not statistically significant. However, this method appears to have applications for enantioselective pharmacokinetic studies of racemic drugs.

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Multi-Rate TCP Video Streaming for Client Heterogeneity (이종 클라이언트들을 위한 멀티레이트 TCP 비디오 스트리밍에 관한 연구)

  • Jung, Young-H.;Choe, Yoon-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.3B
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    • pp.144-151
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    • 2008
  • In this paper, we propose a video streaming server that guarantees a certain level of quality when a server should serve video streaming service to multiple heterogenous clients simultaneously with TCP transport. If each heterogeneous client requests video streaming service in according to its own requirement such as bitrate of content and these requests are accepted by a server, then TCP flows for each video streaming session fairly share limited uplink bandwidth of the server. At this time, because TCP's bandwidth fair-share characteristics can result in bandwidth shrinkage of higher bitrate video streaming session, the client of higher bitrate video may suffer sluggish playback which is related with streaming QoS degradation. To tackle this problem, our proposed server system uses multiple TCP connections adaptively for each video streaming session depending on the anticipated status of the client playout buffer. Simulation results show that our proposed algorithm can successfully reduce the occurrence of playout buffer underrun and enhance streaming quality for whole video clients.