• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.1076-1084
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• 1995

A mixture of aluminum isopropoxide (Al(OC3H7i)3) solution and sodium hydroxide (NaOH) solution was hydrolyzed in the range between pH 1~14. the powder obtained from sol-gel process was calcined at several temperatures and crystallization behaviors of various samples were investigated. The hydrolyzed sols of pH 1~6 wre clear, or near clear. On the other hand, powder precipitated from sols of pH 7~14. The sample obtained from pH 3 solution crystallized via complicated route, and $\beta$-Al2O3 and $\beta$"-Al2O3 phases appeared at lower temperature than samples from other pH conditions. And the quantity of remained $\beta$"-Al2O3 phase after heat treatment at 150$0^{\circ}C$ was more than samples from other pH conditions. After sintering, ionic conductivities were 1.3$\times$10-4S.cm-1 to 0.76$\times$10-4S.cm-1.0-4S.cm-1.

• Journal of the Korean Ceramic Society
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• v.34 no.9
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• pp.957-962
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• 1997

Dicalcium silicate has many polymorphs according to temperature. $\beta$-dicalcium silicate which exists in cement is stabilized by minor components drived from raw materials regardless of temperature, such as high temperature and room temperature. K2O, SO3 and B2O3 are effective stabilizers for $\beta$-dicalcium silicate at room temperature. B2O3 was the most effective stabilizer. Transformation from $\beta$ to ${\gamma}$ phase causes dicalcium silicate to change volume, resulting in dusting phenomenon. When B2O3 was used the phase transformation is the least than any other stabilizers. In addition, the starting temperature of quenching influences phases transformation : low temperature of quenching presented much phase transformation and decreased size of parameter of $\beta$-dicalcium silicate.

• Natural Product Sciences
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• v.6 no.3
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• pp.135-138
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• 2000

MeOH extract of Cuscuta chinensis seeds was fractionated with n-hexane, EtOAc and BuOH successively, and antioxidant activities were tested for all fractions using DPPH free radical scavenging method. In the tested fractions, EtOAc fraction showed high antioxidant activity$(EC_{50},\;50\;{\mu}g)$ From the EtOAc fraction, five compounds have been isolated. On the basis of spectral data, these compounds were identified as ${\beta}-sitosterol$, methyl 4-hydroxy-3,5-dimethoxycinnamate, ${\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside$, caffeic acid, quercetin, kaempferol and calycopteretin. Among these compounds, ${\beta}-sitosterol$ and ${\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside$ showed no antioxidant activity. $EC_{50}$ values of methyl 4-hydroxy-3,5-dimethoxycinnamate, caffeic acid, quercetin, kaempferol and calycopteretin were 0.6, 8, 19, 17 and $12\;{\mu}g$, respectively.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.73-77
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• 1986

Anthraquinones, physcion (I), mp $204{\sim}205^{\circ}$ and emodin (II), mp $254{\sim}255^{\circ}$, and $emodin-8-O-{\beta}-{_D}-glucoside$ (IV), mp $191{\sim}192^{\circ}$ together with ${\beta}-sitosterol$ glucoside (III), mp $280{\sim}282^{\circ}$ were isolated from the roots of Polygonum ellipticum Migo and P. sachalinense Fr. Schm. (Polygonaccae). Stilbene derivatives, 3,5,4'-trihydroxystibene (V), mp $258{\sim}260^{\circ}$ and $3,5,4'-trihydroxystilbene-3-O-{\beta}-{_D}-glucoside$ (VI), mp $142{\sim}144^{\circ}$ were also isolated.

• Journal of the Korean Ceramic Society
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• v.23 no.1
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• pp.67-73
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• 1986

SiC and $SiC-Si_3N_4$ powder were synthesized via the carbiding and carbiding-nitriding reaction of Jecheon quartz respectively using graphite as a reducing agent. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbiding-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $H_2$ atmosphere. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbidint-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $N_2-H_2$ atmosphere. The ratio of $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ content in a produced composite could be controlled by adjusting the reaction time and gaseous mixture.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.282-288
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• 1995

The sutdies were carried out to evaluate the consituents in the rihzomes of the cultivated Korean Rhubarb (Polygonaceae). From the acetone fraction ofl methanol extract Compound I (1, 8-dihydroxy-3-methyl anthraquinone, chrysophanic acid), Compound II($chrysophanol-8-O-{\beta}-D-glucopyranoside$), Compound III ($emodin-8-O-{\beta}-D-glucopyranoside$) and Compound IV ($aloe-emodin-8-O-{\beta}-D-glucopyranoside$), and from the ether fraction Compound V(1, 8-dihydorxy-3-emthyl-6-methoxy anthraquinone, physcion) and Compound VI (1, 6, 8-thitydroxy-3-emthyl anthrauinone, emodin), and also from the n-buthanol fraction Compound VII ($rhapontigenin-3-O-{\beta}-D-glucopyranoside, rhaponticin$) and Compound VIII ($piceatannol-3'-O-{\beta}-D-glucopyranoside$), were isolated and identified on the basis of their physico-chemical and spectroscopic evidences (UV, IR, H-NMR, C-NMR, EI-MS), respectively.

• KSBB Journal
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• v.16 no.4
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• pp.409-414
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• 2001

Biosynthesis of curdlan( ${\beta}$-1,3 glucan) was shown by fluorscence on cellufluor medium. The highest production of curdlan was produced when glucose was used as a carbon source and ($NH_4$)$_2$$SO_4$ was used as a nitrogen source. ${\beta}$ -form of curdlan was detected in the fingerprint region (890 $cm^{-1}$) by FT-IR spectrum and shown homogeneous ${\beta}$ -1,3 glucan by $^{13}C$ NMR spectrum ($C_1$-103 ppm, $C_2$-73.2 ppm, $C_3$-86.4 ppm, $C_4$-68.7 ppm, $C^{5}$-76.63 ppm, $C_{6}$-61.2 ppm). Transition of structure from triple helix coil form to random coil form was appeared at 0.1 ∼0.25 M NaOH concentration. It was shown that natural curdlan is a triple helix form in neutral but becomes weak in alkaline condition.

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.161-176
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• 2018

Fungal ${\beta}$-glucan, known to have immunostimulatory and antitumor activities, can be recognized by host immune cells as one of the pathogen-associated molecular patterns (PAMPs). Although there are several reports on the diverse immunostimulatory activities of ${\beta}$-glucan, little is known about the intracellular signal transduction of ${\beta}$-glucan. Stimulation of RAW264.7 macrophage cells with ${\beta}$-glucan from Ganoderma lucidum induced the expressions of dectin-1, toll-like receptor 2 (TLR2), TLR4, and TLR6 at the transcription stage. Treatment with ${\beta}$-glucan also induced inflammatory mediators such as macrophage inflammatory proteins (MIP)-$1{\alpha}$, MIP-$1{\beta}$, MIP-$1{\gamma}$, interleukin (IL)-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$. Treatment of the cells with polymyxin B, an inhibitor of lipopolysaccharides (LPS), blocked the induction of inflammatory mediators in LPS- or ${\beta}$-glucan-stimulated systems. Pretreatment of the cells in our cell culture system with LY294002, a phosphoinositide 3-kinase (PI3K) inhibitor, or U0126, a mitogen-activated protein kinase/extracellular-signal-regulated kinase (MAPK/ERK) kinase (MEK)1/MEK2 inhibitor, led to a reduction in the induction of inflammatory mediators in a concentration-dependent manner. These results show that stimulation of the macrophage cells by ${\beta}$-glucan induced the expressions of both dectin-1 and TLRs. We also found that the PI3K/Akt and MEK pathways were involved in the induction of inflammatory mediators in macrophage cells during intracellular signal transduction of ${\beta}$-glucan.

• Transactions on Electrical and Electronic Materials
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• v.2 no.1
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• pp.27-31
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• 2001

$\beta$-$In_2S_3$ and $\beta$-$In_2S_3$:$Co^{2+}$ thin films were grown using the spray pyrolysis method. The thin films crystallized into tetragonal structures. The indirect energy band gap of the thin films was found to be 2.32 eV for $\beta$-$In_2S_3$ and 1.81 eV for $\beta$-$In_2S_3$:$Co^{2+}$(Co:1.0 mol%) at 198K. The direct energy band gap was found to be 2.67 eV for $\beta$-$In_2S_3$ and 2.17 eV for $\beta$-$In_2S_3$:$Co^{2+}$(Co:1.0 mol%). Impurity optical absorption peaks were observed for the ${\beta}$-$In_2S_3$:$Co^{2+}$ thin films. These impurity absorption peaks are assigned, based on the crystal field theory, to the electron transitions between the energy levels of the $Co^{2+}$ ion sited in $T_{d}$ symmetry.

• IMMUNE NETWORK
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• v.14 no.6
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• pp.321-327
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• 2014

TGF-${\beta}$ induces IgA class switching by B cells. We previously reported that Smad3 and Smad4, pivotal TGF-${\beta}$ signal-transducing transcription factors, mediate germline (GL) ${\alpha}$ transcription induced by TGF-${\beta}1$, resulting in IgA switching by mouse B cells. Post-translational sumoylation of Smad3 and Smad4 regulates TGF-${\beta}$-induced transcriptional activation in certain cell types. In the present study, we investigated the effect of sumoylation on TGF-${\beta}1$-induced, Smad3/4-mediated $GL{\alpha}$ transcription and IgA switching by mouse B cell line, CH12F3-2A. Overexpression of small ubiquitin-like modifier (SUMO)-1, SUMO-2 or SUMO-3 did not affect TGF-${\beta}1$-induced, Smad3/4-mediated $GL{\alpha}$ promoter activity, expression of endogenous $GL{\alpha}$ transcripts, surface IgA expression, and IgA production. Next, we tested the effect of the E3 ligase PIASy on TGF-${\beta}1$-induced, Smad3/4-mediated $GL{\alpha}$ promoter activity. We found that PIASy overexpression suppresses the $GL{\alpha}$ promoter activity in cooperation with histone deacetylase 1. Taken together, these results suggest that SUMO itself does not affect regulation of $GL{\alpha}$ transcription and IgA switching induced by TGF-${\beta}1$/Smad3/4, while PIASy acts as a repressor.