• Title/Summary/Keyword: Alpha phase

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Expression of Growth Factors and Secretory Leukocyte Protease Inhibitor (SLPI) in RAW264.7 Cells after Lipopolysaccharide (LPS) Stimulation (대식세포주 (RAW264.7)에서 박테리아성 지질다당류 (LPS) 자극에 의한 분비백혈구단백분해효소억제제 (SLPI)와 성장인자들의 발현)

  • Son, Wook-Hee;Choi, Baik-Dong;Jeong, Soon-Jeong;Wang, Guan-Lin;Hwang, Ho-Keel;Jeong, Moon-Jin
    • Applied Microscopy
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    • v.37 no.2
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    • pp.93-102
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    • 2007
  • Secretory leukocyte protease inhibitor (SLPI) was known as one of bacterial lipopolysaccharide (LPS)-induced products of macrophage. Macrophages play an important role in the development of inflammatory responses by secreting an array of cytokines and chemokines in a tissue microenvironment. To identify the function and relationship between potent growth factors and SLPI after LPS stimulation, we conducted reverse transcriptase polymerase chain reaction (RT-PCR) and Western blots for the detection of mRNA and protein expression of SLPI and growth factors such as VEGF, PDGF, bFGF after 100 ng LPS stimulation on the RAW264.7 cells. The result of RT-PCR was showed SLPI mRNA expression was increased from 60 min to 48h in RAW 264.7 cells after incubation with LPS. VEGF and PDGF mRNA was expressed highly at initial stage by LPS stimulation. The mRNA of bFGF and type I collagen was very weakly expressed after LPS stimulation. SLPI protein level was increased likely the mRNA levels in RAW 267.7 cells. Additionally, phase contrast and scanning electron microscopic observation demonstrated that the LPS induce the change of morphology of the RAW264.7 cells. From these results, it suggest that expression of SLPI by LPS treatment may associate with VEGF and PDGF expression in RAW264.7 cells.

Absence of Tocotrienol Form of Vitamin E in Purple Perilla (Perilla frutescens var. acuta Kudo) Seeds Confirmed by Comparative Analysis Using HPLC and GC (GC 및 HPLC 비교분석에 기초한 차조기 종실내 tocotrienol 부재의 평가)

  • Lee, Young-Sang;Kim, Min-Kyoung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.spc
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    • pp.115-120
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    • 2008
  • Lipid soluble vitamin E consists of tocopherols and tocotrienols depending upon double bonds in phytyl side chains attached to chromanol ring. Recent reports on antioxidative, anticancer, and cholesterol-lowering effects of tocotrienols have increased researches and commercialization of tocotrienols. Purple perilla (Perilla frutescens var. acuta Kudo) has been reported as a plant containing tocotrienols along with tocopherol forms of vitamin E based upon normal phase HPLC analysis. To confirm the existence or absence of tocotrienol form of vitamin E in purple perilla, comparative analysis using HPLC, GC/FID, and GC/MSD has been conducted for 14 purple perilla genetic accessions collected from Korea and Japan. Normal phase HPLC analysis showed ${\alpha}-$, ${\beta}-$, ${\gamma}-$, and ${\delta}-tocopherols$ along with peaks with retention times quite similar to ${\beta}-$ and ${\gamma}-tocotrienols$. Same purple perilla samples, analysed by GC exhibited ${\alpha}-$, ${\beta}-$, ${\gamma}-$, and ${\delta}-tocopherols$ quantitatively equivalent to HPLC results. However, no peaks for ${\beta}-$ and ${\gamma}-tocotrienols$ could be observed and unknown two peaks of similar retention times with ${\beta}-$ and ${\gamma}-tocotrienols$ were identified not corresponding tocotrienols by GC/MSD. These results suggest the absence of tocotrienol form of vitamin E in purple perilla as well as the necessity of using GC-based qualitative and quantitative vitamin E analysis to avoid misinterpretation of peaks with similar retention times as tocotrienol isomers when analysed by an HPLC.

Volatile Substances and Physicochemical Characteristics of Pyroligneous Liquor (목초액의 휘발성 성분과 이화학적 특성)

  • Kim Jong-Soo;Park Seung-Woo;Choi Jung-Hwan;Lee Eun-Young;Lee Sang-Han;Chung Shin-Kyo
    • Food Science and Preservation
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    • v.12 no.6
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    • pp.656-661
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    • 2005
  • To develop food additives from pyroligneous liquor, we first examined the physicochemical characteristics of volatile substances. The pH, gravity, acidity, solution tar, and scorched remains in the pyroligneous liquor were 2.50, 1.020, $0.8\%$ $2.31\%$ and $0.008\%$ respectively. The main compounds of pyroligneous liquor were 2,6-dimethoxyphenol (syringol), 2-hydroxy-2-cyclopenten-l-one, 1,2-benzenediol (catechol), phenol, 2 (5H)-furanone, 2-methoxyphenol (guaiacol), 5-hydroxymethyl-2 furancarboxaldehyde were found in organic phase, whereas catechol, 1,4 : 3,6-dianhydro-${\alpha}d$-glucopyranose, cyclopropyl carbinol, 5-hydroxymethyl-2 furancarboxaldehyde in aqueous phase.

Sintering and Electrical Properties of Cr-doped ZnO-Bi2O3-Sb2O3 (Cr을 첨가한 ZnO-Bi2O3-Sb2O3계의 소결과 전기적 특성)

  • Hong, Youn-Woo;Shin, Hyo-Soon;Yeo, Dong-Hun;Kim, Jin-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.12
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    • pp.942-948
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    • 2010
  • In this study we aims to examine the effects of 0.5 mol% $Cr_2O_3$ addition on the reaction, microstructure development, resultant electrical properties, and especially the bulk trap and interface state levels of ZnO-$Bi_2O_3-Sb_2O_3$ (Sb/Bi=0.5, 1.0, and 2.0) systems (ZBS). The samples were prepared by conventional ceramic process, and characterized by XRD, density, SEM, I-V, impedance and modulus spectroscopy (IS & MS) measurement. The sintering and electrical properties of Cr-doped ZBS (ZBSCr) systems were controlled by Sb/Bi ratio. Pyrochlore ($Zn_2Bi_3Sb_3O_{14}$) was decomposed more than $100^{\circ}C$ lowered on heating in ZBS (Sb/Bi=1.0) by Cr doping. The densification of ZBSCr (Sb/Bi=0.5) system was retarded to $800^{\circ}C$ by unknown Bi-rich phase produced at $700^{\circ}C$. Pyrochlore on cooling was reproduced in all systems. And $Zn_7Sb_2O_{12}$ spinel ($\alpha$-polymorph) and $\delta-Bi_2O_3$ phase were formed by Cr doping. In ZBSCr, the varistor characteristics were not improved drastically (non-linear coefficient $\alpha$ = 7~12) and independent on microstructure according to Sb/Bi ratio. Doping of $Cr_2O_3$ to ZBS seemed to form $Zn_i^{..}$(0.16 eV) and $V^{\bullet}_o$ (0.33 eV) as dominant defects. From IS & MS, especially the grain boundaries of Sb/Bi=0.5 systems were divided into two types, i.e. sensitive to oxygen and thus electrically active one (1.1 eV) and electrically inactive intergranular one (0.95 eV) with temperature.

Conformation and Biological Activity of the Neuropeptide $\gamma$ (Neuropeptide $\gamma$의 구조 및 생리활성)

  • Ku Hee-Jung;SEO Jung-Kil;KIM Eun-Hi;HUH Min-Do;CHUNG Joon-Ki;PARK Jang-Su;KANG Shin-Won;PARK Nam Gyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.2
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    • pp.244-251
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    • 1997
  • The relationship between structure and biological activity was studied on the three neuropeptides (mammalian, trout- and goldfish-neuropeptide $\gamma$) that were syntheized by the solid-phase method. Circular dichroism spectra showed that mammalian, trout- and goldfish-neuropeptide $\gamma$ adopted an unordered structure in buffer solution. In the-presence of neutral and acidic liposomes, mammalian and trout-neuropeptioe $\gamma$ also took a random structure. However, goldfish-neuropeptide $\gamma$ took an $\alpha-helical$ structure in acidic liposomes. The intestinal motility response was investigated with carp intestines, guinea-pig ileums and rat duodenums. In case of carp intestine, contractile activity was as follows : goldfish-neuropeptide $\gamma\simeq$ trout-neuropeptide $\gamma>$ mammalian-neuropeptide $\gamma$, On the other hand, the contractile activity of mammalian-neuropeptide $\gamma$ was more potent than trout- and goldfish-neuropeptide $\gamma$ in the guinea-pig ileums and rat duodenums. These results suggest that neuropeptide $\gamma$ show the species-specific activity.

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Fabrication and densification of Heusler Fe2VAl alloy powders by mechanical alloying (MA법에 의한 Heusler Fe2VAl 합금분말의 제조 및 치밀화)

  • Kim, Kwang-Duk;Lee, Chung-Hyo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.1
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    • pp.51-57
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    • 2013
  • We have applied mechanical alloying (MA) to produce Heusler $Fe_2VAl$ thermoelectric alloy using a mixture of elemental $Fe_{50}V_{25}Al_{25}$ powders. An optimal milling and heat treatment conditions to obtain the single phase of Fe2VAl compound with fine microstructure were investigated by X-ray diffraction and differential scanning calorimetry (DSC) measurement. The $Fe_{50}V_{25}Al_{25}$ MA sample ball-milled for 60 hours exhibits a bcc ${\alpha}$-(Fe,V,Al) solid solution. Single phase of Heusler $Fe_2VAl$ compound can be obtained by MA of $Fe_{50}V_{25}Al_{25}$ mixture for 60 hours and subsequently heated up to $700^{\circ}C$. Sintering of the MA powders was performed in a spark plasma sintering (SPS) machine using graphite dies at $900{\sim}1000^{\circ}C$ under 60 MPa. The Vickers hardness of bulk sample sintered at $1000^{\circ}C$ was high value of Hv 870. All compact bodies have a high relative density above 90 % with metallic glare on the surface.

Corrosion behaviors of Cp-Ti and Ti-6Al-4V alloys by TiN coating (TiN 코팅된 Ti 및 Ti-6Al-4V합금의 부식거동)

  • Lee, Soon-Hyun;Jung, Yoong-Hun;Choi, Han-Chul;Ko, Yeong-Mu
    • Journal of Technologic Dentistry
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    • v.30 no.1
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    • pp.25-31
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    • 2008
  • Cp-Ti and Ti-6Al-4V alloys commonly used dental implant materials, particularly for orthopaedic and osteosynthesis because of its suitable mechanical properties and excellent biocompatibility. This alloys have excellent corrosion behavior in the clinical environment. The first factor to decide the success of dental implantation is sufficient osseointegration and high corrosion resistance between on implant fixture and its surrounding bone tissue. In this study, in order to increase corrosion resistance and biocompatibility of Cp-Ti and Ti-6Al-4V alloy that surface of manufactured alloy was coated with TiN by RF-magnetron sputtering method. The electrochemical behavior of TiN coated Cp-Ti and Ti-6Al-4V alloy were investigated using potentiodynamic (EG&G Co, PARSTAT 2273. USA) and potentiostatic test (250mV) in 0.9% NaCl solution at 36.5 $\pm$ 1$^{\circ}C$. These results are as follows : 1. From the microstructure analysis, Cp-Ti showed the acicular structure of $\alpha$-phase and Ti-6Al-4V showed the micro-acicular structure of ${\alpha}+{\beta}$ phase. 2. From the potentiodynamic test, Ecorr value of Cp-Ti and Ti-6Al-4V alloys showed -702.48mV and -319.87mV, respectively. Ti-6Al-4V alloy value was higher than Cp-Ti alloy. 3. From the analysis of TiN and coated layer, TIN coated surface showed columnar structure with 800 nm thickness. 4. The corrosion resistance of TiN coated Cp-Ti and Ti-6Al-4V alloys were higher than those of the non-coated Ti alloys in 0.9% NaCl solution from potentiodynamic test, indicating better protective effect. 5. The passivation current density of TiN coated Cp-Ti and Ti-6Al-4V alloys were smaller than that of the noncoated implant fixture in 0.9% NaCl solution, indicating the good protective effect resulting from more compact and homogeneous layer formation.

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LOW ATMOSPHERE RECONNECTIONS ASSOCIATED WITH AN ERUPTIVE SOLAR FLARE

  • MOON Y.-J.;CHAE JONGCHUL;CHOE G. S.;WANG HAIMIN;PARK Y. D.;CHENG C. Z.
    • Journal of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.41-53
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    • 2004
  • It has been a big mystery what drives filament eruptions and flares. We have studied in detail an X1.8 flare and its associated filament eruption that occurred in NOAA Active Region 9236 on November 24,2000. For this work we have analyzed high temporal (about 1 minute) and spatial (about 1 arcsec) resolution images taken by Michelson Doppler Imager (MDI) onboard the Solar and Heliospheric Observatory, Hoc centerline and blue wing ($-0.6{\AA}$) images from Big Bear Solar Observatory, and 1600 ${\AA}$ UV images by the Transition Region and Corona Explorer (TRACE). We have found that there were several transient brightenings seen in H$\alpha$ and, more noticeably in TRACE 1600 ${\AA}$ images around the preflare phase. A closer look at the UV brightenings in 1600 ${\AA}$ images reveals that they took place near one end of the erupting filament, and are a kind of jets supplying mass into the transient loops seen in 1600 ${\AA}$. These brightenings were also associated with canceling magnetic features (CMFs) as seen in the MDI magnetograms. The flux variations of these CMFs suggest that the flux cancellation may have been driven by the emergence of the new flux. For this event, we have estimated the ejection speeds of the filament ranging from 10 to 160 km $s^{-1}$ for the first twenty minutes. It is noted that the initiation of the filament eruption (as defined by the rise speed less than 20 km $s^{-1}$) coincided with the preflare activity characterized by UV brightenings and CMFs. The speed of the associated LASCO CME can be well extrapolated from the observed filament speed and its direction is consistent with those of the disturbed UV loops associated with the preflare activity. Supposing the H$\alpha$/UV transient brightenings and the canceling magnetic features are due to magnetic reconnect ion in the low atmosphere, our results may be strong observational evidence supporting that the initiation of the filament eruption and the preflare phase of the associated flare may be physically related to low-atmosphere magnetic reconnection.

Development and Characterization of Trans Free Margarine Stock from Lipase-Catalyzed Interesterification of Avocado and Palm Oils (팜유와 아보카도유로부터 효소적 interesterification을 통한 trans free margarine stock 제조 및 이화학적 특성 연구)

  • Lee, Yun-Jeung;Lee, Ki-Teak
    • Korean Journal of Food Science and Technology
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    • v.41 no.3
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    • pp.231-237
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    • 2009
  • Trans free margarine stock (TFMS) was produced by lipase-catalyzed synthesis of fully hydrogenated soybean oil (FHSBO), avocado oil (AO) and palm oil (PO). A blend of FHSBO, AO, and PO with a 1:5:4 (30:150:120 g, respectively) ratio was interesterified with lipozyme RM IM(from Rhizomucor miehei) in a 1 L-batch type reactor at 65 for 12 hr, and the physicochemical and melting properties of TFMS were compared with commercial margarine. The solid fat content (%) of the TFMS was analyzed at 25, 30, and $35^{\circ}C$, respectively, while its melting point was $37.8^{\circ}C$. The trans fatty acid content of the TFMS was below 0.1%. It also had acid, saponification, and iodine values of 0.4, 173.9, and 58.6, respectively. In HPLC chromatograms of the TFMS, newly synthesized peaks of triacylglycerol molecules were observed by using reverse-phase HPLC with evaporative light-scattering detection. Normal-phase HPLC with UV detection was used to quantify tocopherols in the TFMS, indicating that its ${\alpha}-$, ${\gamma}-$ and ${\delta}$-tocopherol contents were 5.7, 2.1, and 1.7 mg/100 g, respectively.

Magnetoresistance characteristics of EeN/Co/Cu/Co system spin-valve type multilayer (FeN/Co/Cu/Co계 spin-valve형 다층악의 자기저항 특성)

  • 이한춘;송민석;윤성호;김택기
    • Journal of the Korean Magnetics Society
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    • v.10 no.5
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    • pp.210-219
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    • 2000
  • The magnetoresistance characteristics of FeN/Co/Cu/Co and FeN/Co/Cu/Co/Cu/Co/FeN multilayers using ferromagnetic iron-nitrides (FeN) has been studied. The microstructure of FeN film is the mixed ${\alpha}$-Fe and $\varepsilon$-Fe$_3$N phase on the condition that the flow rate of N$_2$ gas is over 0.4 sccm. The magnetoresistance effect is observed because of shape magnetic anisotropy induced by needle-shaped $\varepsilon$-Fe$_3$N phase. This magnetoresistance effect changes, because the degree that the shape magnetic anisotropy adheres to the adjacent Co pinned layer is varied according to the flow rate of N$_2$ gas and the thickness of FeN film. The best magnetoresistance effect is obtained on the condition that the thickness of Co free layer is 70 ${\AA}$ and the maximum MR ratio(%) value of 3.2% shows in the FeN(250 ${\AA}$)/Co(70 ${\AA}$)/Cu(25 ${\AA}$)/Co(70 ${\AA}$)/Cu(25 ${\AA}$)/Co(70 ${\AA}$)/FeN(250 ${\AA}$) mutilayer film which is fabricated at the N, gas flow rate of 0.5 sccm and the FeN film thickness of 250 ${\AA}$. Four steps are observed in the magnetoresistance curve owing to this difference of coercive force, because respective magnetic layers in the multilayer possess different coercive forces. These effects observed in these mutilayer films can be expected to application to the memory device the same MRAM as can carry out simultaneously four signals.

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