• Title/Summary/Keyword: ${\beta}$-phase

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Physico-Chemical Properties of Pseudoceramide in Relation to Bilayer-Forming

  • Jeong, Min-Woo;Oh, Seong-Geun;Kim, Do-Hoon;Kang, Hak-Hee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.27 no.1
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    • pp.3-15
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    • 2001
  • The bilayer forming ability of pseudo-ceramide PC104 in octanoic acid/water/n-octyl $\beta$-D-glucoside mixtures was investigated through the phase diagram. Because of its low solubility in water and of its crystallization, pseudoceramide PC104 was dissolved in octanoic acid, which is nontoxic additive for foods and cosmetics. The mixtures formed four different phases (L1, L2, LC and two phases). Depending on the concentration of PC104 in octanoic acid, the region of each phase was extended or contracted. On the contrary to the region of L2, regions of lamellar phase and L1 phase were expanded. The bilayer-forming ability of PC104 was explained on the basis of concentration of PC104 at interface and interaction between PC104 and octanoic acid. From FT-IR results, it was found that the interactions of PC104’s polar head group with octanoic acid increased as the amount of PC104 in octanoic acid increased. Also emulsion size and size distribution have been studied depending upon the emulsification path. droplets of emulsion prepared from lamellar phase were smaller and more homogeneous compared to those of emulsions formed from L2 phase.

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Study of Phase Transition of Copper(II)-phthalocyanine using a Near Field Scanning Microwave Microscope (근접장 마이크로파 현미경을 이용한 Copper(II)-phthalocyanine의 Phase Transition 연구)

  • Park, Mie-Hwa;Yoo, Hyun-Jun;Yun, Soon-Il;Lim, Eun-Ju;Lee, Kie-Jin;Cha, Deok-Joon;Lee, Young-San
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.6
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    • pp.641-646
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    • 2004
  • We report the changes of the microwave reflection coefficients S$_{11}$ of copper(II)-phthalocyanine (CuPc) thin films by using a near-field microwave microscope(NSMM) in order to understand the phase transition of CuPc. For a NSMM system, a high-quality microstrip resonator coupled with a dielectric resonator was used. CuPc thin films were prepared on the pre-heated glass substrates using a thermal evaporation method. The reflection coefficients S$_{11}$ of CuPc thin films were changed by the dependence on the substrate pre-heating temperatures. By comparing reflection coefficient S$_{11}$ and crystal structures, we found the phase transition of CuPc thin films from $\alpha$-phase to $\beta$-phase at the substrate heating temperature 200 $^{\circ}C$./TEX>.

Properties of SiC Electrocondutive Ceramic Composites according to Transition Metal (천이금속 영향에 따른 SiC계 도전성 세라믹 복합체의 특성)

  • Shin, Yong-Deok;Oh, Sang-Soo;Jeon, Jae-Duck;Park, Young;Yim, Seung-Hyuk;Lee, Dong-Yoon
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1588-1590
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    • 2004
  • The composites were fabricated, respectively, using 61vol.% SiC - 39vol.% $TiB_2$ and using 61vol.% SiC 39vol.% WC powders with the liquid forming additives of 12wt% $Al_2O_3+Y_2O_3$ by pressureless annealing at 1800$^{\circ}C$ for 4 hours. Reactions between SiC and transition metal $TiB_2$, WC were not observed in this microstructure. The result of phase analysis of composites by XRD revealed SiC(6H), $TiB_2$ and YAG($Al_5Y_3O_{12}$) crystal phase on the SiC-$TiB_2$, and SiC(2H), WC and YAG($Al_5Y_3O_{12}$) crystal phase on the SiC-WC composites. ${\beta}{\rightarrow}{\alpha}$-SiC phase transformation was ocurred on the SiC-$TiB_2$, but ${\alpha}{\rightarrow}{\beta}$-SiC reverse transformation was not occurred on the SiC-WC composites. The relative density, the flexural strength showed respectively value of 96.2%, 310.19Mpa in SiC-WC composites. The electrical resistivity of the SiC-$TiB_2$ and the SiC-WC composites is all positive temperature cofficient resistance(PTCR) in the temperature ranges from 25$^{\circ}C$ to 500$^{\circ}C$.

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Direct Analysis of the Transcription of Escherichia coli rnpB Gene Harbored in a Multicopy Plasmid during Bacterial Growth

  • Park, Jeong-Won;Jung, Young-Hwan;Park, Bo-Hyun;Jeoung, Yeon-Hee;Lee, Young-Hoon
    • BMB Reports
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    • v.29 no.3
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    • pp.221-224
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    • 1996
  • To examine the growth-phase dependent control of Escherichia coli rnpB gene we used a combination of Northern analysis for RNA determination and Southern analysis for plasmid DNA determination. The relative amounts of metabolically unstable transcript derived from the internally deleted rnpB gene harbored on a multicopy plasmid as well as the relative plasmid contents were measured by Northern analysis and Southern analysis, respectively, of total nucleic acids from E coli cells containing the plasmid. The relative transcription activity of the rnB was represented by a ratio of the relative amount of the transcript to that of the plasmid DNA during bacterial growth. The rnpB transcription increased rapidly with time during exponential growth, but started to decrease before the transition period of an exponential growing cell culture into the stationary phase. Although the expression pattern was similar to the changes of ${\beta}-galactosidase$ activity expressed from the lysogenic strain carrying the chromosomal rnpB-lacZ fusion which were shown in a previous work, the present data appears to represent a more actual growth-phase control of the rnpB transcription than the previous data by the ${\beta}-galactosidase$ assay. In addition the present method described for a direct analysis of both RNA and plasmid DNA provides a rapid and efficient method that can applied to an examination of transcription control by using a multicopy plasmid.

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Comparative Pharmacokinetics of Platinum Coordination Complexes in Rats

  • Insook Jung;Lee, Juseon;Kim, Myungsoo;Changbae Jin;Younsoo Sohn;Park, Jongsei
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.243-243
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    • 1996
  • 백금착물 항암제 후보물질로서 합성된 KBP31705-Cl27, KBP30603-901을 기존 화합물인 cisplatin 및 carboplatin과 pharmacokinetic profile을 비교 검토하였다. 웅성 Sprague-Dawley rat을 sodium pentobarbital 마취하에서 방광 및 대퇴동맥과 정맥에 polyethylene tubing을 사용하여 catheterization시켰다. Urine 배출이 안정화되었을 때 대퇴정맥내로 cisplatin과 KBP31705-Cl27은 2 mg/kg, carboplatin과 KBP 30603-901은 20mg/kg 용량으로 주사한 후 2, 4, 6, 8, 10, 15, 20, 30, 45, 60, 120 분에 대퇴동맥으로부터 혈액을 채취하였으며 urine은 약물투여 후 1시간 간격으로 4시간동안 채취하였다. Plasma와 urine중의 platinum농도는 inductively coupled plasma-mass spectrometer를 사용하여 측정하였고, pharmacokinetic parameters는 non-linear least square computer Program인 PCNONLIN을 이용하여 산출되었다. 혈중 platinum농도와 시간의 관계에서 KBP31705-Cl27은 cisplatin과 비교하여 alpha-phase에서 혈중 농도는 낮지만 비슷한 양상을 나타내었고, beta-phase에서는 비교적 느리게 소실됨을 보였다. Urine으로 4시간동안 배출된 platinum양은 각각 투여량의 52, 56%로서 두 약물에서 비슷하였다. 또한 KBP30603-901은 carboplatin과 비교하여 alpha-phase는 거의 비슷한 패턴을 나타내었으나, beta-phase는 훨씬 느리게 감소하여 반감기가 길다는 것을 보여 주었으며 또한 이것은 urine으로 4시간동안 배출된 platinum양이 KBP30603-901의 경우 투여량의 46%로서 carboplatin의 59%보다 적게 배출된다는 data와도 일관됨을 보여주었다. 이상의 결과로 볼 때 KBP30603-901이 다른 백금착물 항암제보다 체내에 머무르는 시간이 길어 혈중에서 보다 오랜 시간동안 머물러 높은 유효농도를 유지할 수 있을 것으로 사료된다.

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Application of 3-dimensional phase-diagram using FactSage in C3H8-SiCl4-H2 System (C3H8-SiCl4-H2 시스템에서 FactSage를 이용한 압력-조성-온도 3차원 상평형도의 응용)

  • Kim, Jun-Woo;Kim, Hyung-Tae;Kim, Kyung-Ja;Lee, Jong-Heun;Choi, Kyoon
    • Journal of the Korean Ceramic Society
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    • v.48 no.6
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    • pp.621-624
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    • 2011
  • In order to deposit a homogeneous and uniform ${\beta}$-SiC films by chemical vapor deposition, we constructed the phase-diagram of ${\beta}$-SiC over graphite and silicon via computational thermodynamic calculation considering pressure(P), temperature(T) and gas composition(C) as variables in $C_3H_8-SiCl_4-H_2$ system. During the calculation, the ratio of Cl/Si and C/Si is maintained to be 4 and 1, respectively, and H/Si ratio is varied from 2.67 to 15,000. The P-T-C diagram showed very steep phase boundary between SiC+C and SiC region perpendicular to H/Si axis and also showed SiC+Si region with very large H/Si value of ~6700. The diagram can be applied not only to the prediction of the deposited phase composition but to compositional variation due to the temperature distribution in the reactor. The P-T-C diagram could provide the better understanding of chemical vapor deposition of silicon carbide.

Partition Coefficient of Proteins of Different Surface Hydrophobicity in Poly (ethylene glycol)-Dextran Aqueous Two Phase System (Poly(ethylene glycol)-Dextran 수용액 2상계에서 단백질들의 소수성에 따른 분획계수)

  • Lee, Sam-Pin;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.19 no.2
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    • pp.140-145
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    • 1987
  • The partition coefficient of the proteins of known effective hydrophobicity was determined in a poly (ethylene glycol)-dextran aqueous two-phase system. The changes in the partition coefficient was also determined when a fraction of PEG-palmitate (PEG-P) was added to the system. The partition coefficient of the proteins increased as the concentrations of PEG and dextran increased at a constant phase volume ration irrespective of the effective hydrophobicity of the proteins. When small amounts of PEG-P were added to the PEG phase, the partition coefficients of BSA and ${\beta}-lactoglobulin$, which had relative hydrophobicity (RI) of 700 and 120, respectively, increased more than ten-fold, whereas ovalbumin whose RI was 5 showed little change. The drastic increases m the partition coefficient were observed by the addition of PEG-P in 2% level to the PEG system. Addition of PEG-P over 5% level resulted in a slight further increase in the partition coefficient of all proteins tested.

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Microstructure and Mechanical Properties of Mg-Li Powder by Hot Rolling Process

  • Choi, Jeong-Won;Kim, Yong-Ho;Kim, Jung-Han;Yoo, Hyo-Sang;Woo, Kee-Do;Kim, Ki-Beom;Son, Hyeon-Taek
    • Korean Journal of Materials Research
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    • v.25 no.1
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    • pp.32-36
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    • 2015
  • Hot rolling of Mg-6Zn-0.6Zr-0.4Ag-0.2Ca-(0, 8 wt%)Li powder was conducted at the temperature of $300^{\circ}C$ by putting the powder into the Cu pipe. The microstructure and mechanical properties of the samples were observed. Mg-6Zn-0.6Zr-0.4Ag-0.2Ca without Li element was consisted of ${\alpha}$ phase and precipitates. The microstructure of the 8 wt%Li containing alloy consisted of two phases (${\alpha}$-Mg phase and ${\beta}$-Li phase). In addition, $Mg_2Zn_3Li$ was formed in 8%Li added Mg-6Zn-0.6Zr-0.4Ag-0.2Ca alloy. By addition of the Li element, the non-basal planes were expanded to the rolling direction, which was different from the based Mg alloy without Li. The tensile strength was gradually decreased from 357.1 MPa to 264 MPa with increasing Li addition from 0% to 8%Li. However, the elongation of the alloys was remarkably increased from 10 % to 21% by addition of the Li element to 8%. It is clearly considered that the non-basal texture and ${\beta}$ phase contribute to the increase of elongation and formability.

Comparison of Volatile Compounds Identified in Different Parts of Peucedanum japonicum Thunberg by Harvest Time (방풍나물의 수확시기에 따른 부위별 향기성분 비교 분석)

  • Jung, Bok-Mi;Shin, Tai-Sun;Heo, Young-Ran
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.12
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    • pp.1871-1880
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    • 2014
  • Headspace volatile compounds of leaf, stem, and root of Peucedanum japonicum Thunberg (PJT) harvested in March and July were isolated, separated, and identified by using a combined system of solid phase microextraction and gas chromatography/mass spectrometry. Identified numbers of volatile compounds were 72, 75, and 63 in March PJT as well as 78, 73, and 69 in July, respectively. Total compounds identified from PJT consisted of alcohols (1~7), aldehydes (7~15), esters (1~4), hydrocarbons (5~9), ketones (1~2), monoterpenes (13~16), monoterpene alcohols (1~5), monoterpene aldehydes (2~4), monoterpene esters (1~4), monoterpene ketones (1~2), sesquiterpenes (16~24), and miscellaneous compounds (2~3). Major volatile compounds of PJT were monoterpenes at all harvest times and in all parts of PJT. The amounts of ${\beta}$-pinene in leaf and stem harvested in March were highest in monoterpenes, followed by ${\alpha}$-pinene and ${\beta}$-myrcene. However, amounts of volatile compounds of monoterpenes in leaf and stem from July PJT were in the decreasing order of ${\beta}$-pinene, ${\beta}$-phellandrene, and ${\beta}$-myrcene. Of the 39 sesquiterpenes identified in PJT, (E)-caryophyllene in March leaf was the most abundant volatile compound, followed by acoradiene in March leaf, ${\beta}$-elemene, and ${\alpha}$-copaene in July stem.

Effect of Clitocybin A on the Proliferation of Dermal Papilla Cells (Clitocybin A의 모유두 세포증식 효능)

  • Kang, Jung-Il;Kim, Min-Kyoung;Yoo, Eun-Sook;Yoo, Ick-Dong;Kang, Hee-Kyoung
    • Korean Journal of Pharmacognosy
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    • v.45 no.4
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    • pp.288-293
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    • 2014
  • The present study was conducted to evaluate the hair growth-promoting effect of Clitocybin A from mushroom Clitocybe aurantiaca with dermal papilla cells (DPCs), which play important roles in the regulation of hair cycle. Clitocybin A significantly increased the proliferation of immortalized rat vibrissa DPCs. Flow cytometry analysis revealed that Clitocybin A promoted cell-cycle progression through G0/G1 to S phase in immortalized rat vibrissa DPCs. In addition, Clitocybin A increased the level of cell cycle proteins such as cyclin D1, phospho-pRB, and phospho-CDK2. To elucidate the molecular mechanisms of Clitocybin A on the proliferation of DPCs, we examined the activation of wnt/${\beta}$-catenin signaling which is known to regulate hair follicle development, differentiation and hair growth. Clitocybin A activated wnt/${\beta}$-catenin signaling via the increase of phospho(ser552)-${\beta}$-catenin, phospho(ser675)-${\beta}$-catenin and phospho(ser9)-$GSK3{\beta}$. Furthermore, Clitocybin A markedly increased the activation of extracellular signal-regulated kinase (ERK). These results suggest that the Clitocybin A may induce hair growth by proliferation of DPCs via cell-cycle progression as well as the activation of Wnt/${\beta}$-catenin signaling and ERK pathway.