• Title/Summary/Keyword: MgB2

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Studies on Artificial Control of Parturition in Korean Native Goats IV. The Effects of Dexamethasone and(or) Estradiol-Benezoate to Induction of Parturition (한국재래산양 분만의 인위적 조절에 관한 연구 IV. Dexamethasone 단독 및 Estradiol-Benzoate와의 병용투여에 의한 분만유기 효과)

  • 윤창현;성환후;오석두;장규태
    • Korean Journal of Animal Reproduction
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    • v.16 no.3
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    • pp.231-237
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    • 1992
  • The effects to the corticosteroid dexamethasone(DEX) and(or) estradiol-benzoate(E-B) treated to induction of parturition and birth weights of the young was conducted in 48 pregnant Korean native goats. The animals were divided into 4 goats per each treatment by the time(142, 145 and 148 day of pregnancy) and dosage(DEX 15, 20mg, DEX 8mg+E-B 10mg and DEX 13mg+E-B 7.5mg per goat). The results obtained were summarized as follows: 1 The time for induction of parturtion after DEX(15, 20mg) treatment on day 148 of pregnancy was significantly(P<0.01) shorter than 142 and 145 days. There was no significant difference each dosage of DEX on same day of pregnancy. 2. The addition of E-B to DEX treatment compared with DEX alone group at day 142 and 145 of pregnancy were significantly(P<0.01) shorter the time for induction of parturition. However, treatment with DEX along or with E-B on 148 day of pregnancy did not affect the time to induction(about 27 hrs) of parturition between each treatment. 3. The birth weight of kids after parturition was heaviest(P<0.01) on day 148 of pregnancy. However, development and vigor of kids were not significant different between DEX alone treatment and with E-B.

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Changes in Carbohydrate, Phenolics and Polyamines of Pepper Plants under Elevated-UV-B Radiation (자외선 조사에 의한 고추 유묘의 탄수화물 합성과 항산화물질 변화)

  • Sung, Jwa-Kyung;Lee, Su-Yeon;Park, Jae-Hong;Lee, Sang-Min;Lee, Yong-Hwan;Choi, Du-Hoi;Kim, Tae-Wan;Song, Beom-Heon
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.1
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    • pp.38-43
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    • 2008
  • Pepper plants (Capsicum annuum, cv. Manitta) were subjected to different intensities of UV-B radiation to understand alterations of primary- and secondary-metabolism such as carbohydrates, phenolic compounds and polyamines. UV-B doses with a UV-B lamp ($1.2W\;m^{-2}$) were adjusted between 0 to 9 hr. The soluble sugars and starch contents in pepper leaves were highly influenced by UV-B treatment. The soluble sugars altered from $6.7mg\;g^{-1}\;fw$ to $5.2mg\;g^{-1}\;fw$ after 9 hrs of UV-B exposure. The starch contents after 3 hrs of UV-B exposure changed from $17.7mg\;g^{-1}\;fw$ to $12.3mg\;g^{-1}\;fw$ and then remained unchanged. The absorbance of UV-absorbing compounds reached initially maximum at all wavelengths read. On the basis of this result, we analyzed total phenolics, anthocyanin and simple free phenolic acids. Anthocyanin and free phenolic acids responded sensitively with a steady increase during UV-B treatment, although anthocyanin contents declined highly after 3 hrs of treatment. Whereas, there is no alteration of total phenolics (as gallic acid equivalent) caused by UV-B. Free polyamine levels in leaves increased rapidly and highly when UV-B was treated. The most prominent changes in polyamine induction were putrescine and spermidine (+ 70 %) after 3 hrs and spermine (+ 150 %) after 6 hrs.

Effect of $B_2O_3$ on the Microstructure and the Microwave Dielectric Properties of the $Ba(Mg_{1/3}Ta_{2/3})O_3$ Ceramics ($Ba(Mg_{1/3}Ta_{2/3})O_3$ 세라믹의 미세구조 및 고주파 유전 특성에 대한 $B_2O_3$의 영향)

  • Kim, Beom-Jong;Kim, Mi-Han;Lee, Woo-Sung;Park, Jong-Chul;Lee, Hwak-Joo;Nahm, Sahn
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.772-775
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    • 2004
  • 본 논문에서는 $B_2O_3$ 첨가가 Ba$(Mg_{1/3}Ta_{2/3})O_3$ (BMT)의 유전특성 및 미세구조의 변화에 미치는 영향에 대해 연구하였다 $B_2O_3$가 소량 첨가되었을 때는 결정립의 성장을 야기하여 치밀한 미세구조를 보였지만, 다량이 첨가된 경우 비정상 결정립 성장을 야기하여 치밀화가 떨어지는 미세구조를 보임과 동시에 $Ba_3Ta_5O_{15}$의 2차상을 형성했다. 이는 소량의 $B_2O_3$ 첨가가 유전특성의 향상을 가져왔지만, 다량의 첨가는 오히려 특성의 악화를 가져온 결과의 원인이라 생각된다. 0.5mol%의 $B_2O_3$를 첨가하여 $1500^{\circ}C$에서 6시간 소결한 경우 ${{\varepsilon}_r}=24$, $Q{\times}f=210,000GHz$의 유전 특성 값과 $4.74ppm/^{\circ}C$$T_{cf}$ 값을 얻었다.

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Vitamin B-6 Nutritional Status of Breast-fed and Formula-fed Preterm Infants (모체의 비타민 B-6 섭취상태가 조산아의 비타민 B-6 영양상태에 미치는 영향)

  • 강순아
    • Journal of Nutrition and Health
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    • v.28 no.4
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    • pp.321-330
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    • 1995
  • Concentrations of total vitamin B-6 in human milk as well as individual, B-6 vitamers have important implications for the nutritional management of breast-fed(BF) infants. Vitamin B-6 status was assessed in 3 groups of infants : two groups preterm (PT) BF infants whose mothers were supplemented with 2 or 27mg pyridoxine(PN)-HCI ; a sub group of formula-fed (FF) PT infants. Mothers and infants were assessed weekly during the 28-day post feeding. Throughout the neonatal period, levels of total vitamin B-6 and percentages of pyridoxal(PL) in breast milk were lower in PT than T mothers, even in mothers supplemented with 27mg PN-HCI. Total vitamin B-6 levels in PT milk paralleled maternal supplementation but percentage distributions of B-6 vitamers did not change. Vitamin B-6 intakes of BF preterm infants paralleled their mothers' level of infants in the 2mg group was suggested by vitamin status parameters. Vitamin B-6 inadequacy of infants correlated with their plasma pyridoxal-5-phosphate(PLP) levels and erythrocyte alanine aminotransferase(E-ALAT) activity; all parameters such as plasma PLP, PL/PLP ratio and stimulation % of E-ALAT were highest for FF PT infants. The positive correlation of vitamin B-6 levels in breast milk gestational age may contraindicate its adequacy for some PT infants.

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Advanced Regeneration and Genetic Transformation of Lycium chinense Harboring Salt Tolerance Genes (구기자나무 (Lycium chinense)의 효과적인 재분화 및 내염성 유전자가 도입된 형질전환체의 개발)

  • 이진숙;권기원;배창휴;양덕춘
    • Korean Journal of Plant Tissue Culture
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    • v.28 no.1
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    • pp.47-52
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    • 2001
  • Bet A and Bet B genes related to salt resistance were introduced into Lycium chinense through high efficiencies of plant regeneration. The explants were precultured on the shooting medium which is consisted of MS medium added 1mg/L kinetin and 0.05mg/L IBA for 2 days. After pre-culture, they were immersed in LB media containing Agrobacteria tumefaciens harboring Bet genes, and cultured on the same medium. Putative transformants could be selected after cocultivation of the explants with Agrobacteria on the shooting medium supplemented with 30mg/L kanamycin. The presence of both Bet A and Bet B genes from the transgenic plants were confirmed by PCR amplification with the gene specific primers and subsequent PCR-Southern blot with labeled Bet genes probe. The expression of Bet A and Bet B genes in the transgenic plants were observed by RT-PCR method.

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Effects of Plant Water Extract Codonopsis Lanceolatae on Mouse Immune Cell Activation Ex Vivo (더덕 물 추출물의 경구 투여가 마우스 면역 세포 활성에 미치는 효과)

  • Ryu, Hye-Sook;Kim, Kyoung-Ok;Kim, Hyun-Sook
    • Journal of Nutrition and Health
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    • v.42 no.3
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    • pp.207-212
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    • 2009
  • Codonopsis lanceolatae has been used as one of the traditional remedies as well as food source. However, few studies on their immunomodulating effects have been reported. We previously reported that ex vivo supplementation of Codonopsis lanceolatae water extracts enhanced splenocyte proliferation compared to the control group. In order to elucidate its ex vivo effect, six to seven week old balb/c mice were fed ad libitum on a chow diet and water extracts of Codonopsis lanceolatae were orally administrated every other day for four weeks at two different concentrations (50 and 500 mg/kg B.W). After preparing the single cell suspension, the proliferation of splenocytes was determined by MTT (3- [4,5-dimethylthiazol-2-y] -2,5-diphenyl terazolium bromide) assay. The production of cytokine (IL-1${\beta}$, IL-6, TNF-${\alpha}$), secreted by macrophages stimulated with LPS or not, was detected by ELISA assay using a cytokine kit. After 48 hrs of incubation with the mitogen (ConA or LPS) stimulation, the mice splenocyte proliferation in experimental group was statistically increased at two different concentrations than that in control group. The cytokines production was more significantly enhanced at the lower supplementation (500 mg/kg B.W.) group rather than higher concentration (500 mg/kg B.W.) compared to the control group. The results of this study may suggest that the supplementation of water extract of plant mixture could regulate the immune function by increasing the splenocyte proliferation and enhance the immune function through regulating cytokine production capacity by activated macrophages in mice.

Synthesis of Tungsten Boride using SHS(Self-propagating High-temperature Synthesis) and Effect of Its Parameters (자전연소 합성법을 이용한 W-B 화합물 합성 및 조건 변수의 영향)

  • Choi, Sang-Hoon;Nersisyan, Hayk;Won, Changwhan
    • Korean Journal of Materials Research
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    • v.24 no.5
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    • pp.249-254
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    • 2014
  • Due to their unique properties, tungsten borides are good candidates for the industrial applications where certain features such as high hardness, chemical inertness, resistance to high temperatures, thermal shock and corrosion. In this study, conditions were investigated for producing tungsten boride powder from tungsten oxide($WO_3$) by self-propagating high-temperature synthesis (SHS) followed by HCl leaching techniques. In the first stage of the study, the exothermicity of the $WO_3$-Mg reaction was investigated by computer simulation. Based on the simulation experimental study was conducted and the SHS products consisting of borides and other compounds were obtained starting with different initial molar ratios of $WO_3$, Mg and $B_2O_3$. It was found that $WO_3$, Mg and $B_2O_3$ reaction system produced high combustion temperature and radical reaction so that diffusion between W and B was not properly occurred. Addition of NaCl and replacement of $B_2O_3$ with B successfully solved the diffusion problem. From the optimum condition tungsten boride($W_2B$ and WB) powders which has 0.1~0.9 um particle size were synthesized.

Studies on the Penetration, Diffusion Ability and Effect of Insects Control Using the Methyl Bromide in the Vertical Silo (수직사이로에 있어 MB훈증제의 침투확산성 및 살충효과 시험)

  • Hah J.K.;Kim J.T.;CHO N.K.;Kim B.H.
    • Korean journal of applied entomology
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    • v.20 no.4 s.49
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    • pp.212-216
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    • 1981
  • This experiment was carried out to investigate the penetration velocity and diffusion ability of methyl bromide fumigants under the condition of natural gravity, and the effect of in control of yellow corn in the vortical silo. The results were as fallows 1. The methyl bromide remainded concentration on the surface of the vertical silo was rapidly reduced from over 100mg/l to under 20mg/l, within 2 hours after supplying methyl bromide fumigant 2. Even 3m depth place from the surface of the vertical silo filled with yellolw corn was well penetrated within 30 minutes, but its remained methyl bromide gas was reduced gradually from over 100mg/l to 30mg/l after 12 hours duration. 5. In case of 13m place tile penetration ability of methyl bromide was over 100mg/l within one hour and kept the same concentration of it for 12 hours, its remainded methyl bromide preserved over 40mg/l until 48 duration time. 4. Less methyl bromide gas was detected at the bottom place than 3m and 13m depth of the vertical silo. It showed bellow 20mg/l of methyl bromide gas only through the whole duration time. 5. Comparing to the vertical penetration velocity of mehtyl bromide gas, the horizontal diffusion ability was not so good. Therefore, remained methyl bromide gas of 3m depth at the wall side of silo was about half than that of center circle where the nearer place from the methyl bromide supplying point, and the methyl bromide gas of 13m depth placed center circle was detected about 15 to 20 times than that of wall side. 6. For the purpose of examining the mortality of methyl bromide, the testing insects (Lesser Rice weevil and confused flour beetle) placed on the surface and bottom side of the silo were killed completely after 24 hrs fumigation, and the same results showed also at the 3m, 7m and 13m depth after 48 hrs fumigation.

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Effect of Additives on the Characteristics of Amorphous Nano Boron Powder Fabricated by Self-Propagating High Temperature Synthesis (자전연소합성법을 이용한 비정질 나노 붕소 분말 특성에미치는 첨가제의 영향)

  • Joo, Sin Hyong;Nersisyan, Hayk H.;Lee, Tae Hyuk;Cho, Young Hee;Kim, Hong Moule;Lee, Huk Hee;Lee, Jong Hyeon
    • Korean Journal of Materials Research
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    • v.25 no.12
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    • pp.659-665
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    • 2015
  • The self-propagating high temperature synthesis approach was applied to synthesize amorphous boron nano-powders in argon atmospheres. For this purpose, we investigated the characteristics of a thermally induced combustion wave in the $B_2O_3+{\alpha}Mg$ system(${\alpha}=1.0-8.0$) in an argon atmospheres. In this study, the exothermic nature of the $B_2O_3-Mg$ reaction was investigated using thermodynamic calculations. Experimental study was conducted based on the calculation data and the SHS products consisting of crystalline boron and other compounds were obtained starting with a different initial molar ratio of Mg. It was found that the $B_2O_3$ and Mg reaction system produced a high combustion temperature with a rapid combustion reaction. In order to regulate the combustion reaction, NaCl, $Na_2B_4O_7$ and $H_3BO_3$ additives were investigated as diluents. In an experimental study, it was found that all diluents effectively stabilized the reaction regime. The final product of the $B_2O_3+{\alpha}Mg$ system with 0.5 mole $Na_2B_4O_7$ was identified to be amorphous boron nano-powders(< 100 nm).

A Novel Method for Measurements of the Penetration Depth of $MgB_2$ Superconductor Films by Using Sapphire Resonators with Short-Circuited Parallel Plates (Short-Circuited 평행판 사파이어 공진기를 이용한 $MgB_2$ 초전도체 박막의 침투깊이 측정법)

  • Jung, Ho-Sang;Lee, J.H.;Cho, Y.H.;Seong, W.K.;Lee, N.H.;Kang, W.N.;Lee, Sang-Young
    • Progress in Superconductivity
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    • v.10 no.2
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    • pp.116-122
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    • 2009
  • We introduce a measurement method that enables to measure the penetration depth($\lambda$) of superconductor films by using a short-ended parallel plate sapphire resonator. Variations in the $\lambda$ of $MgB_2$ films could be measured down to the lowest temperature using a sapphire resonator with a $YBa_2Cu_3O_{7-x}$ film at the bottom. A model equation of $\lambda=\lambda_0[1-(T/T_c)^{\tau}]^{-1/2}$ for $MgB_2$ films appeared to describe the observed variations of the resonant frequency of the sapphire resonator with temperature, with $\lambda_0,\;\tau$, and $T_C$ used as the fitting parameters.

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