• Journal of the Korean Vacuum Society
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• v.7 no.4
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• pp.361-367
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• 1998

$\alpha$-Sexithiophene ($\alpha$-6T) thin films were deposited by organic molecular beam deposition (OMBD) technique. The $\alpha$-6T was synthesized and purified by the sublimation method. The thin films of the $\alpha$-6T were deposited under various deposition conditions. The effects of deposition rate, substrate temperature, and vacuum pressure on the formation of these films have been studied. The molecular orientation, crystallinity, and surface morphology of $\alpha$-6T films were investigated with angle-resolved UV/visible absorption spectroscopy, X-ray diffractometry (XRD), and atomic force microscopy (AFM). It was found that the crystalline structure of $\alpha$-6T films was monoclinic and independent uppon substrate temperature, deposition rate, and deposition pressure. On the other hand, the $\alpha$-6T molecules in the film deposited at a low deposition rate, higher substrate temperature, and under a high vacuum tended to be aligned perpendicular to the substrate.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.180-185
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• 1997

Sikye was produced from glutinous rice. The glutinous rice Sikhye was found to contain 7.3% of limit dextrin, 10.1% of maltose, 1.3% of maltotriose and 1.75% of rice residue. Limit dextrin in glutinous rice Sikhye was purified by ethanol fractionation followed by gel chromatography on Biogel P-2. The purified limit dextrin showed both signal of $\alpha$-1,4- and $\alpha$-1,6-glucosidic linkage with its estimation ratio of 5:1 by 1H-NMR analysis. Limit dextrin was digested with enzymes(30units/ml) of $\alpha$-amylase, $\alpha$-glucosidase and glucoamylase from Aspergillus awamori, sweet potato $\beta$-amylase and human salivary $\alpha$-amylase at 37$^{\circ}C$ for 1 hour, respectively. Hydrolysis rates of these amylases on it were similar that of rice Sikhye. $\alpha$-Glucosidase plus human salivary $\alpha$-amylase hydrolyzed it to 18%. The results suggest that glutinous rice is more effective to produce high level of branched maltooligosaccharide compared with rice as raw material for Sikye making.

• Journal of The Korean Astronomical Society
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• v.51 no.1
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• pp.5-16
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• 2018

We investigate the escape of $Ly{\beta}$ from emission nebulae with a significant population of excited hydrogen atoms in the level n = 2, rendering them optically thick in $H{\alpha}$. The transfer of $Ly{\beta}$ line photons in these optically thick regions is complicated by the presence of another scattering channel leading to re-emission of $H{\alpha}$, alternating their identities between $Ly{\beta}$ and $H{\alpha}$. In this work, we develop a Monte Carlo code to simulate the transfer of $Ly{\beta}$ line photons incorporating the scattering channel into $H{\alpha}$. Both $H{\alpha}$ and $Ly{\beta}$ lines are formed through diffusion in frequency space, where a line photon enters the wing regime after a fairly large number of resonance scatterings with hydrogen atoms. Various line profiles of $H{\alpha}$ and $Ly{\beta}$ emergent from our model nebulae are presented. It is argued that the electron temperature is a critical parameter which controls the flux ratio of emergent $Ly{\beta}$ and $H{\alpha}$. Specifically for $T\;=\;3{\times}10^4\;K$ and $H{\alpha}$ line center optical depth $\tau{\alpha}\;=\;10$, the number flux ratio of emergent $Ly{\beta}$ and $H{\alpha}$ is ~ 49 percent, which is quite significant. We propose that the leaking $Ly{\beta}$ can be an interesting source for the formation of $H{\alpha}$ wings observed in many symbiotic stars and active galactic nuclei. Similar broad $H{\alpha}$ wings are also expected in $Ly{\alpha}$ emitting halos found in the early universe, which can be potentially probed by the James Webb Telescope in the future.

• Journal of Aquaculture
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• v.9 no.1
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• pp.57-63
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• 1996

The relative effectiveness of steroids and human chorionic gonadotropin (HCG) on germinal vesicle breakdown (GVBD) was investigated in vitro using the isolated oocytes (folliculated oocytes) from the spotted halibut, Verasper variegatus. Among the steroids tested, $17\alpha-hydroxy,\;20\beta-dihydroprogesterone\;(17\alpha20{\beta}OHP)$ was more effective than progesterone (P4) and $17\alpha-hydroxyprogesterone\;(17{\alpha}OHP$). In comparing $17\alpha,\;20{\beta}OHP$ with HCG, both $17\alpha20{\beta}OHP$ and HCG were effective in inducing GVBD at all concentrations : $17\alpha20{\beta}OHP$ was effective even at lower concentrations ($10\~50$ ng/ml). HCG at three concentrations used (50, 100, 500 IU/ml) showed no significant differences in inducing GVBD.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.342-347
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• 2003

The enzyme $20{\alpha}$-hydroxysteroid dehydrogenase ($20{\alpha}$-HSD) catabolizes progesterone to $20{\alpha}$-dihydroprogesterone ($20{\alpha}$-OHP), and is appeared in rat corpora luteal and placenta. A polled samples of 10-15 placental and ovarian tissues collected from each individual rat were subjected to measurement of $20{\alpha}$-HSD activity. A $20{\alpha}$-HSD activity in the cytosol fraction was based on the generation of NADPH. In this study, it is designed to study cytosolic $20{\alpha}$-HSD activity in rat ovarian and placenta during pregnancy, and its relationship to embryonic mortality. It was found that from days 5 to 18 of pregnancy the $20{\alpha}$-HSD activities steady by decreased but at parturition time rapidly increased in ovary. On the other hand, placental cytosolic $20{\alpha}$-HSD activities were high detected from days 8 to 10 of pregnancy, not detectable from days 11 to 20 of pregnancy, but again very high at the time of parturition. Analysis of DEAE column chromatography revealed that two different types of $20{\alpha}$-HSD (HSD-1 and HSD-2) were found with similar activity in the placental cytosol on day 10 of pregnancy. The number of fetuses on day 10 of pregnancy was 15.4 and decreased significantly to 12.9 on day 12. The results suggested that expression of $20{\alpha}$-HSD in the placental tissues seems to be related the number of fetal survived in the specific time (days 11 and 12) which spontaneous fetal loss occurs.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.52-56
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• 1999

This study has examined the effects of Aralia elata Seemann ethanol extract on antioxidant enzyme systems inrats along with benzo($\alpha$) pyrene(B(a)P) administration . The ethanol extract of Aralia elata Seemann (50mg/kg body wt.) was fed to rats for 4 weeks by stomach tubing. The extract administration increased antioxidant activities of glutathione sulfur transferase(GST) comparing to the control. also total superoxide dismutase(SOD) and Cu, Zn-SOD activities were stimulated. Catalase activities were increased by 50% with the extract feeding compared to the control . Combined administration of B($\alpha$)P and the extract increased GST activity in B($\alpha$) P group. Although total SOD acitivity was decreased , Cu, Zn-SOD was greately increased from 0.10unit to 0.18 unit and catalase activity also was increased compared to the group of B($\alpha$) P. GST activity in CLE group was 1.32 unit, increased by 33% comparing to the group CL of 0.99unit. Cu, Zn-SOD and catalase activities in thegroup fed high fat and ethanol extracts were increased by 25% and 39%, respectivley comparing to the group of high fat. In addition , total SOD was decreased but, Cu, Zn-SOD acitivity was increased from 0.09 unit to 0.18unit. Catalase activity was 76.05 unit in the group of B($\alpha$) P and extract comparing to 65.26 units in B($\alpha$)P group. Serum $\alpha$-tocopherol of rat was markedly increased by theextract. Administration of B9$\alpha$)P reduced $\alpha$-tocopherol levels in the serum, on the other hand, lard in the diet increased $\alpha$-tocopherol levels in the serum. The above results indicate that Aralia bud exerts antioxidant functions in vivo against B($\alpha$)P. Further research may be necessary for the identification fo the biologically active material.

• Journal of Biomedical Engineering Research
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• v.26 no.4
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• pp.223-230
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• 2005

This paper presents a new approach to investigate spatial correlation between independent components of brain alpha activity in functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). To avoid potential problems of simultaneous fMRI and EEG acquisitions in imaging pure alpha activity, data from each modality were acquired separately under a 'three conditions' setup where one of the conditions involved closing eyes and relaxing, thus making it conducive to generation of alpha activity. The other two conditions -- eyes open in a lighted room or engaged in a mental arithmetic task, were designed to attenuate alpha activity. Using a Mixture Density Independent Component Analysis (MD-ICA) that incorporates flexible non-linearity functions into the conventional ICA framework, we could identify the spatiotemporal components of fMRI activations and EEG activities associated with the alpha rhythm. Then, the sources of the individual EEG alpha activity component were localized by a Maximum Entropy (ME) method that is specially designed to find the most probable dipole distribution minimizing the localization error in sense of LMSE. The resulting active dipoles were spatially transformed to 3D MRls of the subject and compared to fMRI alpha activity maps. A good spatial correlation was found in the spatial distribution of alpha sources derived independently from fMRI and EEG, suggesting the proposed method can localize the cortical areas responsible for generating alpha activity successfully in either fMRI or EEG. Finally a functional connectivity analysis was applied to show that alpha activity sources of both modalities were also functionally connected to each other, implying that they are involved in performing a common function: 'the generation of alpha rhythms'.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.477-486
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• 1991

To elucidate enzymatic properties of a-glactosidase (EC 3.2.1.22) from Asp. niger, a-galactosidase from wheat bran culture was purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. And then its enzymatic propeties were investigated. The highest level of $\alpha$-galactosidase activity was obtained when Asp. niger was grown on wheat bran medium at $30^{\circ}C$ for 96 hours. The $\alpha$-galactosidase was purified by 23.7 fold by ammonium sulfate fractionation, ion exchange chromatography on DEAE-Celluose and Sephadex A-50, and gel filtration on Sephadex G-150 and its specific activity was 1,229 Unitslmg protein and the yield was 14% of the total activity of wheat bran culture. The purified $\alpha$-galactosidase was found to be homogeneous by polyacrylamide gel electrophoresis and HPLC. The $\alpha$-galactosidase was a tetrameric glycoprotein which consisted of identical subunits with molelcular weight of 28,000 each by SDS-PAGE and isoelectric point was determined analytical isoelectric focusing to be pH 4.6. The optimal temperature and pH for the $\alpha$-galactosidase activity were $40^{\circ}C$ and pH 6.5, respectively, and 54% of its activity was lost by heating at $60^{\circ}C$ for 10 mins, It was appeared to have higher affinty to raffinose than to stachyose. The K, value and activation energy of $\alpha$-galactosidase were 5.0 mM and 8.515 Kcal per mole for p-nitrophenyl- $\alpha$--D-galactopyranoside, respectively.

• Biomedical Science Letters
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• v.24 no.3
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• pp.213-220
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• 2018

Triglyceride (TG) is known to be associated with inflammatory disease including atherosclerosis. In a variety of atherosclerosis models, T lymphocytes are localized in the earliest lesions of atherosclerosis. T cell associated cytokines such as $TNF-{\alpha}$ and $IFN-{\gamma}$ have pre-dominant inflammatory effects in chronic vascular diseases. In our previous study, we found that the expression of $TNF-{\alpha}$ and its receptor, $TNF-{\alpha}R$ was increased when Jurkat T lymphocyte cell lines were exposed to TGs. Therefore, experiments were conducted to determine which cell signaling pathway are involved in the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs. To identify signal transduction pathways involved in TG-induced upregulation of $TNF-{\alpha}$, we treated TG-exposed Jurkat T cells with specific inhibitors for MEK1, PI3K, $NF-{\kappa}B$ and PKC. We found that inhibition of the MEK1 pathway blocked TG-induced upregulation of $TNF-{\alpha}$. However, the expression level of $TNF-{\alpha}R$ did not change with any signal transduction inhibitor. Based on this observation, we suggest that increase of exogenous TG induces increase of $TNF-{\alpha}$ expression through MEK1 pathway in Jurkat T cells. In addition, it was confirmed that the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs occurs via different pathways.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.349-354
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• 1985

A 4.7 kb Hind III fragment containing $\alpha$-amylase gene of Bacillus stearothermophilus IAM 11062 was cloned in Escherichia coil HB101, using plasmid pBR322 and runaway plasmid pSY343 as a vector. The cloned gene was stably maintained and expressed In E.coli. The constructed strain of E. coli have at least 3 times higher amylase activity than the donor strain, of B. stearothermophilus. About 75％ of the $\alpha$-amylase produced by the constructed strain of E. coli was localized in the periplasm and it was found that the enzymes can be released by an osmotic shock using EDTA. The enzymatic properties of L-amylase produced in E. coli were very similar to those produced by B. stearothermophilus in terms of optimum temperature, heat stability and molecular weight.