• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.49-55
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• 1997

This study was conducted to establish mass propagation system from the tissue culture using immature embryos in Eleutherococcus senticosus. Immature embryos from seeds were removed under the microscope and placed on MS, $MSB_5\;and\;B_5$ medium containing several plant growth regulators. While the calli were well formed on media containing 2 mg/l of 2, 4-D, 2 mg/l of 2, 4-D and 0.7 mg/l of TDZ, shoot regeneration was better on MS medium with combinations of high concentrations of TDZ and low concentrations of 2, 4-D. Treatment of 2, 4-D alone was better than treatment of TDZ alone in callus induction, but plant regeneration was reversed. The results of callus formation and shoot regeneration on $MSB_5\;and\;B_5$ media were similar to those of MS media. The rate of callus formation was nearly 100% when 2, 4-D was added to $B_5$, medium on concentration of 2 mg/l or 0.7 mg/l. TDZ showed very significant effect on the formation of multiple shoots.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.3-3
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• 2004

• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.119-119
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• 2009

• Progress in Superconductivity
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• v.10 no.1
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• pp.29-34
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• 2008

Magnesium diboride ($MgB_2$) is an inexpensive and simple superconductor. This material was first synthesized and its structure confirmed in 1953 but its superconducting properties were not discovered until 2001 when they caused great excitement. In this study, superconducting $MgB_2$ thin films on the r-$Al_{2}O_3$ substrates have been grown by the combination of radio frequency magnetron sputtering of B and thermal evaporation of Mg. The deposition conditions were varied by changing deposition rate. Before the co-deposition of Mg and B, the deposition rates of each element have been measured separately. The $MgB_2$ layers had 400nm in thickness and superconducting transition temperatures have been measured around $\sim$38.6K. Superconducting properties have been measured by PPMS, XRD, and SEM.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.53-57
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• 2009

The h-BN powder was synthesized by amorphous $B_2O_3$ and activated carbon at $1550^{\circ}C$ in nitrogen atmosphere, whose properties were examined according to $MgB_6$ addition. Amount of $MgB_6$ addition was varied in the range of $0{\sim}$10\;wt% of the initial mixture. It was observed that $MgB_6$ addition led to an increase in the amount and the grain size of h-BN and decrease in the amount of $B_4C$ forming. When $MgB_6$ added 5 wt%, the amount and crystallinity of h-BN increased as the holding time at the synthesis temperature was prolonged. It was also confirmed that the regularity of three-dimensional ordering of h-BN increases.

• Progress in Superconductivity
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• v.10 no.2
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• pp.74-78
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• 2009

Inter-grain nanobridges of the $MgB_2$ superconductor have been fabricated by focused-ion-beam(FIB) and their electrical transport properties were studied. The $MgB_2$ film was prepatterned into microbridges by a standard argon ion milling technique and then FIB-patterned into 100 nm$\times$100 nm bridges. Current-voltage characteristics showed a strong flux-flow type behavior at all temperatures with a trait of Josephson coupling near $T_c$. At low temperatures, the curves showed a two-step resistance-doubled transition with occasional hysteresis. The resistance-doubling transition is believed to be due to a two-channel flux-flow effect. The temperature-dependent critical current data showed $I_c(T){\propto}(1-T/T_c)^2$ near $T_c$, same as a normal barrier junction, and $I_c(T){\propto}(1-T/T_c)^{1.2}$ at low temperatures, similar to that of a film.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.94-99
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• 1997

When the leaf and stem tissues of Rehmannia glutinosa were cultured on MS medium with plant growth regulators, shoots were regenerated on MS medium with TDZ(0.01 to $2.0{\mu}M$), and root initiation was better on MS medium treated with NAA(0.01 to 2.0mg/$\iota$). On $B_5$ medium, shoot regeneration was better on medium with TDZ than those with Quincrac, NAA, and 2.4-D. The addition of Quincrac, NAA, and 2.4-D inhibited shoot regeneration on MS medium, but promoted shoot regeneration on $B_5$ medium. Shoot regeneration and growth was better on MS medium with the combination treatments of 2.4-D 0.01mg/$\iota$ and TDZ 0.01, 0.1 and $2{\mu}M$ compared with other treatments. Also shoot regeneration and growth on B_5 medium showed the similar results to that on MS medium.

• Journal of Community Nutrition
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• v.7 no.2
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• pp.79-84
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• 2005

A vitamin B-6 (B-6) intake higher than the current Recommended Dietary Allowance (RDA) has been found to provide an improvement in immune system. Seven premenopausal women consumed their usual diet with the exception of foods relatively high in vitamin B-6 for a total of 27 d. After 7 d, all subjects received a multivitamin supplement containing 2mg B-6 and 4 subjects were given an additional 50mg of B-6 supplement for 20 d. Lymphocyte response to phytohemagglutinin (PHA) was measured before and after the supplementation. To determine the effect of different forms of B-6 on lymphocyte proliferation, cell culture media supplemented with pyridoxal (PL) and PLP, as well as B-6 free media, were tested. A 50mg B-6 supplement significantly increased vitamin B-6 status. There was no further enhancement on lymphocyte proliferation when subjects were taking an additional 50mg of vitamin B-6 supplement. In general, lymphocyte proliferation in media with either PLP or PL did not show any prominent difference. These [m-dings suggest that there may be no further benefits of a B-6 dose beyond twice that of the current RDA on lymphocyte proliferation. Further studies are necessary to examine the effect of the B-6 intake level on activities of enzymes involved in cellular B-6 metabolism in lymphocytes to provide substantial insight into the mechanisms underlying the role of B-6 in the lymphocyte proliferation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.495-500
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• 1998

To compare the extent of heat treatment in domestic infant formula, pH,titratable acidity, undenatured whey protein contents, HMF contents and protein-reducing substances of three commercial products (A, B, C) were measured. The pH of B products was lowest and the titratable acidity of B product was highest. The contents of undenatured whey protein per 100ml serum were 0∼30mg(A products), 90∼130mg(B products)and 80∼90mg(C products), respectively. Distinct differences of undenatured whey protein contents according to the manufacturer and infat's stage in age could be observed. The HMF contents of tested products showed 10.9∼21.5umol/L and B-2 product(B products for the second stage of 5∼9 month) was the highest among tested products. The protein-reducing substances showed 4.46∼9.50mg K4Fe(CN)6/100ml serum nd B-2 product was the highest among tested products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.502-508
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• 1986

Extracts of six seaweeds obtained from solvents such as water, methanol, hexane and ethyl ether have been tested for desmutagenic activities in the Salmonella typhimurium/microsome systems. Water extracts obtained from tangle, sea-tangle, and gompi were moderately effective on the mutagenicity of Trp-P-2 and aflatoxin $B_1$. Methanol extracts of sea-tangle and gompi were effective against Trp-p-2, and all samples of methanol extracts were very effective from 1.0mg to 2.0mg per plate on the mutagenicity of MeIQ and aflatoxin $B_1$. Hexane extracts of tangle, ses-tangle, gompi and sea-straghorn were very effective on the mutagenicity of Trp-p-2, MeIQ and aflatoxin $B_1$ except laver and green laver. Ethyl ether extracts of gompi and sea-straghorn were most effective from 1.0mg to 2.0mg per plate on the mutagenicity of Trp-P-2. Especially, ethyl ether extracts of all samples were great effective on the mutagenicity of MeIQ and aflatoxin $B_1$.