• 제목/요약/키워드: Buffers

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A Study on the Buffer Effects of Social Support on the Strain of the Aged (노인이 경험하는 긴장상태에 대한 사회적 지원의 완충효과 -노인의 생활만족도를 중심으로-)

  • 이신숙
    • Journal of the Korean Home Economics Association
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    • v.35 no.4
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    • pp.199-210
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    • 1997
  • The purpose of this study was to examine whether social support buffers the deleterious effects of strain on life satisfaction of the aged and to provide information for finding out ways of increasing their life satisfaction. The subjects of this study were 252 aged persons living in Kwangju and Joun-nam. The statistics used for data analysis were frequency percentage mean standard deviation reliablity Pearson's correlation multiple regression analysis through the SAS package program. 1) The support score from family was higher than the support from friends and the total point of life satisfaction of the aged was 28.4 which was above the median 24. 2) Social support especially the support from family buffer the negative effect of strain on life satisfaction of the aged. The result indicates that the family remains a supportive system for the aged parents Therefore A program in necessary for aged parents to promote the emotional solidarity between the aged parents and their children.

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Deposition of Ce$O_{2}$ buffer layer for YBCO coated conductors on hi-axially textured Ni substrate by MOCVD technique (양축 정렬된 Ni기판 위에 MOCVD법에 의한 YBCO 초전도 선재용 Ce$O_{2}$ 완충층의 증착)

  • 김호진;주진호;전병혁;정충환;박순동;박해웅;홍계원;김찬중
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.91-94
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    • 2002
  • Textured Ce$O_{2}$ buffers for YBCO coated conductors were deposited on biaxially textured Ni substrate by metalorganic chemical vapor deposition The texture of deposited Ce$O_{2}$ films was varied with deposition temperature(T) and oxygen partial pressure($Po_{2}$). ($\ell$ 00) textured Ce$O_{2}$ films were deposited at T= 500~$520^{\circ}C$, $Po_{2}$= 0.90~3.33 Torr. The growth rate of the Ce$O_{2}$ films was 150~200 nm/min at T= $520^{\circ}C$ and $Po_{2}$= 2.30 Torr, which was much faster than that prepated by other physical deposition method.

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Water Transport during the Single-pass Perfusion Experiments : Effects of Some Perfusates and Their Osmolality (일회통과 관류실험시 물의 수송 : 관류액의 종류와 삼투압의 영향)

  • 이정화;이현주;용철순;오두만
    • YAKHAK HOEJI
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    • v.39 no.4
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    • pp.411-416
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    • 1995
  • The single-pass perfusion experiments were performed in anesthetized rats to investigate the effects of perfusates and their osmolality on the water transport and to determine the correlation between the extent of water transport and the volume change of perfusate. Phenol red was used as a nonabsorbable marker. In normal rats, when perfused at a flow rate of 0.5 ml/min, 2-(N-rnorpholino) ethanesulfonic acid (MES) and S$\phi$rensen's phosphate buffers showed minimal net water transport as 0.125 and 0.173 %/cm of intestinal length, respectively. Hypotonic perfusate of 200 mOsm/kg of water and hypertonic perfusate of 400 mOsm/kg of water generated significant water transport compared with isotonic perfusate of 300 mOsm/kg of water. There was a linear correlation between the extent of water transport and the volume change of perfusate, suggesting that the volume change can be used as a measure of water transport.

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재조합 E. coli로부터 발현되는 철단백질의 분리 및 정제

  • Park, Hyeon-Gyu;Lee, Ji-Won;Kim, In-Ho
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.697-700
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    • 2001
  • Iron is an essential nutrient for most organisms, which supplied to them in a protein-iron complex known as ferritin. Ferritins are multimeric proteins found in prokaryotes, plants and animals. They are consisted of spherical shell of 24 subunits defining a cavity of about 8nm in diameter, where an iron core is laid down. Expression of ferritin in recombinant E. coli at $37^{\circ}C$ led to the accumulation of recombinant ferritin. Insoluble form of ferritin was separated from disrupted cells, followed by various primary separation steps with two kinds of buffers. Collected samples from the primary steps were purified by DEAE-cellulose gels packed in a column. The fractions from the DEAE column were assayed to gain the amount and the purity of ferritin by using HPLC and SDS-PAGE.

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Refolding and Characterization of Recombinant Fusion Ferritin by Gel Filtration Chromatography

  • Kim, Hyoung-Won;An, Eun-Kyoung;Shin, Mi-Young;Kim, In-Ho
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.544-547
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    • 2003
  • Fusion $ferritin(F_H+F_L),$ an iron-binding protein, was purified from recombinant E. coli by gel filtration chromatography after two-step sonications. Unfolded ferritin was refolded by GFC with various refolding enhancing additives. 50 mM Tris-HCI(pH 7.4) buffers containing 2 M urea and additive was used in GFC. Objective was to characterize the structure change at various conditions. Molecular weight was determined using GF-HPLC and RP-HPLC was used to quantify the unfolded and refolded proteins. Activity was confirmed by iron-uptake reaction.

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Trend of Intel Nonvolatile Memory Technology (인텔 비휘발성 메모리 기술 동향)

  • Lee, Y.S.;Woo, Y.J.;Jung, S.I.
    • Electronics and Telecommunications Trends
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    • v.35 no.3
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    • pp.55-65
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    • 2020
  • With the development of nonvolatile memory technology, Intel has released the Optane datacenter persistent memory module (DCPMM) that can be deployed in the dual in-line memory module. The results of research and experiments on Optane DCPMMs are significantly different from the anticipated results in previous studies through emulation. The DCPMM can be used in two different modes, namely, memory mode (similar to volatile DRAM: Dynamic Random Access Memory) and app direct mode (similar to file storage). It has buffers in 256-byte granularity; this is four times the CPU (Central Processing Unit) cache line (i.e., 64 bytes). However, these properties are not easy to use correctly, and the incorrect use of these properties may result in performance degradation. Optane has the same characteristics of DRAM and storage devices. To take advantage of the performance characteristics of this device, operating systems and applications require new approaches. However, this change in computing environments will require a significant number of researches in the future.

융합 페리틴의 요소 농도에 따른 재접힘 특성에 관한 연구

  • Kim, Hyeong-Won;Sin, Mi-Yeong;An, Eun-Gyeong;Kim, In-Ho
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.480-483
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    • 2003
  • Fusion ferritin$(F_H+F_L)$, an iron-binding protein, was purified from recombinant E. coli by two-step sonications with urea. Unfolded ferritin was refolded by gel filtration chromatography with various concentration of urea. 50 mM Tris-HCl(pH 8.0) buffers with 1 M to 4 M urea were used in GFC. Objective was to characterize the structure change with urea concentration. Molecular weight was determined using GF-HPLC and RP-HPLC was used to quantify the unfolded and refolded proteins.

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FINITE ELEMENT MODEL TO STUDY CALCIUM DIFFUSION IN A NEURON CELL INVOLVING JRYR, JSERCA AND JLEAK

  • Yripathi, Amrita;Adlakha, Neeru
    • Journal of applied mathematics & informatics
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    • v.31 no.5_6
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    • pp.695-709
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    • 2013
  • Calcium is well known role for signal transduction in a neuron cell. Various processes and parameters modulate the intracellular calcium signaling process. A number of experimental and theoretical attempts are reported in the literature for study of calcium signaling in neuron cells. But still the role of various processes, components and parameters involved in calcium signaling is still not well understood. In this paper an attempt has been made to develop two dimensional finite element model to study calcium diffusion in neuron cells. The JRyR, JSERCA and JLeak, the exogenous buffers like EGTA and BAPTA, and diffusion coefficients have been incorporated in the model. Appropriate boundary conditions have been framed. Triangular ring elements have been employed to discretized the region. The effect of these parameters on calcium diffusion has been studied with the help of numerical results.

An Integrated Network Control Framework for the Next-Generation Optical Internet (차세대 광 패킷 인터넷을 위한 통합 네트워크 제어 구조)

  • Park, Sung-Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.8
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    • pp.666-671
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    • 2000
  • With the current advances in optical WDM (Wavelength Division Multiplexing) networking technologies and the increasing demand for network bandwidth the Next Generation Internet is expected to be a network that runs IP(Internet Protocol) directly over WDM-based optical networks. The network control architecture for the IP over WDM networks is different from that of traditional Internet since the underlying WDM devices have more constraints than electronic IP routers such as the lack of optical buffers and wavelength continuity property etc. In this paper we introduce several architectural models for implementing IP over WDM networks and propose an integrated network control framework for the IP over WDM networks. This framework leverages the traffic engineering control architecture for the MPLS (Multi-Protocol Label Switching) networks and is mainly developed for the IP over packet-switched WDM networks. We also report several preliminary simulation results of contention resolution schemes in the packet-switched WDM networks.

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Studies on Oral Absorption of Piperacillin Pivaloyloxymethyl Ester (피페라실린피발로일옥시메칠에스텔의 경구흡수에 관한 연구)

  • Kang, Sung-An
    • Journal of Pharmaceutical Investigation
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    • v.18 no.2
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    • pp.49-53
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    • 1988
  • Pivaloyloxymethyl ester of piperacillin was synthesized by reacting sodium piperacillin with chloromethyl pivalate, and its chemical structure was determined by infrared and $^1H$ nuclear magnetic resonance spectroscopic methods. The pharmaceutical properties of the ester were investigated to assess its potential as a novel prodrug of piperacillin. The interface transfer of piperacillin and the ester was studied in a two-phase in vitro system composed of aqueous pH buffers and n-octanol. The ester was more lipophilic, and less water soluble above pH 4.0 than piperacillin. Significant antibacterial activity was not observed in the ester in vitro, but the ester was hydrolyzed into the parent drug in the rat liver homogenate. The serum levels of orally administered ester suspension containing 0.1% Tween 80 were measured in rabbits. It was found that the ester showed higher blood level, comparing with no observation of piperacillin in serum, but the time reaching the maximum serum concentration was 5 hr.

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