• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.393-402
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• 2021

In this study, a mixed matrix membrane was prepared by putting the zeolitic imidazolate framework-7 (ZIF-7) synthesized in Pebax-1657 and Pebax-2533, which are representative poly(ether-b-amide), and the permeability properties of single gas such as N₂ and CO₂ were investigated. From the gas permeation results, in the case of N₂, both the Pebax-1657/ZIF-7 and Pebax-2533/ZIF-7 mixed matrix membranes showed a similar phenomenon in which the permeability decreased with the incorporation of ZIF-7. For CO₂ permeability, the tendency was slightly different depending on the type of polymer. In the Pebax-1657/ZIF-7 mixed membrane, the CO₂ permeability decreased in the range of 0~3 wt% of ZIF-7, and increased at higher contents. The CO₂ permeability of the Pebax-2533/ZIF-7 mixed matrix membrane gradually decreased without increasing the permeability in the range of 0~5 wt% of ZIF-7. Regarding CO₂/N₂ selectivity, both mixed films showed a tendency to increase with increasing the ZIF-7 content. In particular, Pebax-2533/ZIF-7 5 wt% showed the best gas permeation performance compared to other mixed matrix membrane. This is thought to be because ZIF-7 shows better compatibility with Pebax-2533 than that of Pebax-1657 and also better CO₂ selective property.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.1
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• pp.49-60
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• 2005

The Back Bone of gearing portion between Core Network System which is used in wire and wireless system is No.7 Protocol. ISUP( ISDN User Part), INAP handling in Intelligent Network and MAP gearing method for linking each Network Element System in mobile network have use of No.7 signaling. Therefore, it is require for system to detect the problem - operating problem occurs in Core Network which use No.7 signaling or the existing problem that is not recognized - in shortest time. This paper study out analyzing and measuring system for No.7 protocol and analyzing out system whether out of order or not. It can abstract No.7 Signaling Message and analyze system performance and report it. This system is connected in system No.7 HW Module which is in charge of No.7 Signaling. It is not offer Emulator function and Simulation function for any scenario but offer monitoring No.7 signaling. This system perform the function about No.7 MTP, ISUP, INAP and MAP and is offered several wire and wireless network Operator. It can detect and correct SW system, HW system and operating system problem. From now on, this system may offer the function about A-interface which is gearing between BSC and MSC, so it will perform to analyze generally and prompt effective operating for Core Network system.

• Korean Journal of Animal Reproduction
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• v.15 no.3
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• pp.195-199
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• 1991

This study was carried out ot investigate effect of pH stimulation on acrosome reaction of bovine spermatozoa. The results obtained were as follows : 1. When sperm was sequentially washed with SHP solution of pH 7.4, 7.7 and 7.4 and incubated in mTALP solution of pH 7.4 for 120min, 15, 30, 60 and 120min incubations showed significantly(p<0.05) higher sperm acrosome reaction rate than 0 min. 2. When sperm was sequentially washed with SHP solution of pH 7.4, 8.0 and 7.4 and incubated in mTALP solution of pH 7.4 for 15 minutes, sperm acrosome reaction rate was significantly(p<0.01) increased until 9 min. Incubation, but not increased thereafter. 3. When sperm were separately washed with SHP solutions of pH 7.0, 7.4 and 8.0 and incubated in mTALP solution of pH 7.4 for 9min, sperm acrosome reaction rate was 74.8, 71.8 and 93.4%. pH 8.0 showed signifciantly(p<0.01) higher sperm acrosome reaction rate than pH 7.0 and 7.4. The results suggest that stimulation of sperm with high pH induces sperm crosome reaction.

• Journal of Aquaculture
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• v.21 no.1
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• pp.26-33
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• 2008

This study investigated the synergistic effects of dietary supplementation of quartz porphyry(QP) and a laboratory developed feed stimulants, BAISM(BS) on growth performance and utilization as the additives for juvenile eel Anguilla japonica. Six isoenergetic experimental diets(18.2 kJ/g) were formulated to contain 50% crude protein, 15% lipid with or without dietary QP(Song-Gang stone, Davistone, Korea) and BS supplementation. QP and BS were provided at 0% in the control diet($Q_0B_0$) and at 0.7% QP+0% BS($Q_{0.7}B_0$), 0.7% QP+0.3% BS($Q_{0.7}B_{0.3}$), 0.7% QP+0.5% BS($Q_{0.7}B_{0.5}$), 0.7% QP+0.75% BS($Q_{0.7}B_{0.75}$) and 0.7% QP+1.0% BS($Q_{0.7}B_{1.0}$) in experimental diets on dry matter basis. After four weeks of adaptation, triplicate groups of 30 fish initially averaging $15{\pm}0.1g(mean{\pm}SD)$ were randomly distributed into each aquarium, and they were fed one of the experimental diets for 8 weeks. By the end of the feeding trial, weight gain(%), specific growth rate(%), feed efficiency(%) and protein efficiency ratio of fish fed diet $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$, were significantly higher(P<0.05) than those of fish fed the other diets. But, $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$ were no significant differences(P<0.05). In challenge test, fish were infected by intraperitoneal injection of 0.1 mL bacterial suspension with Edwardsiella tarda per fish after the feeding trial. As a result, fish fed QP and BS supplemented diets have a significantly higher cumulative survival rate than those of fish fed control diet(P<0.05). In conclusion, these results indicated that the optimum dietary supplementation level of QP and BS could be approximately 0.7% quartz porphyry+0.5% BAISM($Q_{0.7}B_{0.5}$) of diet based on WG, FER, SGR, PER, cumulative survival rate in juvenile eel A. japonica.

• Korean Journal of Animal Reproduction
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• v.15 no.1
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• pp.7-13
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• 1991

This study was carried out to investigate the effects of pH of sperm-washing solution, sperm-washing frequency and individual bull on concentration of hydrogen ion in sperm-washed solution and sperm acrosome reaction. The results obtained were as follow. 1. When bovine sperm was washed at 4 times with SHP solution and incubated, the difference of light absorbance between sperm-washing and sperm-washed solution(${\Delta}$Ao-${\Delta}$At) was higher in 2nd sperm-washed solution than that in the other washed solutions. 2. When sperm was thrice washed with SHP solutions of pH 5.99, 6.38, 6.78, 7.10, 7.40, 7.69, 8.15, 8.45, and 8.83, ${\Delta}$Ao-${\Delta}$At was significantly increased at pH7.69 to 8.83, and ${\Delta}$Ao-${\Delta}$At in 1st sperm washed solution was significantly higher than that in 2nd and 3rd sperm washed solution. 3. When sperm of Holstein, KNC and Hereford was thrice washed with SHP solutions of pH 5.99, 6.38, 6.78, 7.10, 7.40, 7.69, 8.15, 8.45, and 8.83, Holstein showed higher ${\Delta}$Ao-${\Delta}$At of sperm Washed solution than KNC and Hereford, and ${\Delta}$Ao-${\Delta}$At in sperm washed solution was significantly increased at 7.69 for Holstein and at 8.15 for KNC and Hereford, respectively. 4. When sperm was thrice with SHP solution of pH 6.8, 7.1 and 7.4, and then incubated in mTALP of pH 7.4 for 15 minutes, in 1st and 2nd sperm washing ${\Delta}$Ao-${\Delta}$At of sperm washed solution was significantly higher at pH 7.1 and 7.4 than at pH 6.8, and the sperm acrosome reaction of pH 6.8, 7.1 and 7.4 was 49.1, 68.8 and 72.9%, respectively. The sperm acrosome reaction of pH 7.1 and 7.4 was higher than that of pH 6.8.

• Applied Microscopy
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• v.29 no.4
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• pp.471-477
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• 1999

Microstructural observations on the pyrochlore-type $Lu_2Ti_2O_7$ and the similar type of compounds, $In_2(Ti_{1.7}Zn_{0.3})O_{6.7}$ and $In_2(Ti_{1.7}Mg_{0.3})O_{6.7}$ which were made by the isothermal heat-treatment at 1623K for 18 days in Pt tube, were carried out using a top-entry HRTEM working at 200 kV. The modulated structures were found in both compounds, however, not in $Lu_2Ti_2O_7$. From the electron diffraction pattern analysis, the modulated superlattices are incommensurate and are 2.69 times of sublattices along (220) direction. The high resolution TEM images have shown that the superlattices consist of alternate superlattices which are composed of two or three sublattices, resulting in the average of 2.7 times of sublattices in accordance with the analysis of electron diffraction patterns. The crystal structures of both compounds are found to quite similar to those of pyrochlore, however the evidence that the cubic axes are slightly deviated from right angle. The modulated structure has gradually changed to the unmodulated structure induced by electron irradiation.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.50-50
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• 2003

We have identified and analysed a putative response regulator two-component gene (CaSKN7) from Candida albicans and its encoding protein (CaSkn7). CaSKN7 has an open reading frame of 1677bp. CaSKN7 encodes a 559 amino acid protein (CaSkn7) with an estimated molecular mass of 61.1 kDa. CaSKN7 is a homologue of a Saccharomyces cerevisiae SKN7 that is the regulator involved in the oxidative stress response. To study the role of CaSKN7, we constructed a CAI4-derived mutant strain carrying a homozygous deletion of the CaSKN7 gene. In the caskn7 disruptant cells, the formation of germ tube require shorter time than that in the congenic wild-type strain but the growth of mycelium delayed in liquid media. In contrast, the caskn7 disruptant cells attenuate the differentiation in solid media and the virulence in mouse model system. Expression level of hypha-specific and virulence genes - HYR1, ECE1, HWP1, and ALS1 - in the caskn7 disruptant cells increased as compared with that in the congenic wild-type strain in 10％ serum YPD. Skn7 in 5. cerevisiae was found to bind the HSE element from the SSA promoter, Also, CaSkn7 contains heat shock factor DNA-binding domain and the promoters of these genes have HSE-like sties. Therefore these results show that CaSKN7 regulate the differentiation and virulence of C. albicans.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.198-203
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• 1999

7S and 11S globulins are two major storage proteins in soybean seed. For improving the quality of soybean seed protein, an increase of 11S/7S ratio would be a desirable objective because 11S globulin contains much more sulfur-containing amino acids than 7S globulin. In this study, six soybean varieties grown at three locations were used for genetic variation analysis of 7S and 11S globulins. It was possible to screen the soybean genotypes having aberrant subunit compositions of the two globulins by a sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). So, heritabilities, genotypic and phenotypic correlations among eight globulin fraction contents of soybean seeds were estimated. The mean value of 7S and 11S globulin fraction contents were 38.9% and 61.1%, respectively, and the ratio of 7S to 11S globulin ranged from 0.58 to 0.74. The high heritability value was found in $\beta$ subunits but the values of acidic and basic subunits were relatively low. Genotypic correlations were higher than the corresponding phenotypic correlations in most of globulin subunit contents. $\beta$ subunits was negatively correlated with $\alpha$ and $\alpha$' subunits among 7S fractions, while no significant correlation between $\alpha$ and $\alpha$' subunits could be found In case of 11S fractions, acidic and basic subunits exhibited no genotypic but negative phenotypic correlation.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.44-55
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• 2016

Bacillus cereus is a gram-positive, rod-shaped, spore-forming bacterium that has been isolated from contaminated fermented soybean food products and from the environment. B. cereus produces diarrheal and emetic toxins and has caused many outbreaks of foodborne diseases. In this study, we investigated whether B. amyloliquefaciens RD7-7, isolated from rice doenjang (Korean fermented soybean paste), a traditional Korean fermented soybean food, shows antimicrobial activity against B. cereus and regulates its toxin gene expression. B. amyloliquefaciens RD7-7 exhibited strong antibacterial activity against B. cereus and inhibited the expression of B. cereus toxin-related genes (groEL, nheA, nheC, and entFM). We also found that addition of water extracts of soybean and buckwheat soksungjang (Korean fermented soybean paste made in a short time) fermented with B. amyloliquefaciens RD7-7 significantly reduced the growth and toxin expression of B. cereus. These results indicate that B. amyloliquefaciens RD7-7 could be used to control B. cereus growth and toxin production in the fermented soybean food industry. Our findings also provide a basis for the development of candidate biological control agents against B. cereus to improve the safety of fermented soybean food products.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.150-150
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• 2000

The adsorption geometry and the electronic property of Mg grown at room temperature on the Si(111)-7$\times$7 surface with various coverages have been studied by scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). At low Mg coverage, the Mg atoms preferentially adsorb at the center adatom sites of the faulted half of the Si(111)-7$\times$7 surface. The adsorbed Mg atom acts as nucleophile with respect to Si atoms thus forms a stable ionic bond with the substrate Si atoms. Above 1 Ml, the 7$\times$7 surface starts to be disrupted and an amorphous Mg overlayer is formed. The LEED shows either $\delta$7$\times$7 or 1$\times$1 pattern at this coverage. When more Mg atoms were exposed, a flat and broad {{{{ { 2} over {3 } }}}}{{{{ SQRT { 3} }}}}$\times${{{{ { 2} over {3 } }}}}{{{{ SQRT { 3} }}}}R30$^{\circ}$region evolves. A flat silicide is formed at first and multi-level Mg islands having hexagonal step edges develop with increasing coverage. The scanning tunneling spectroscopy (STS) confirms the electronic properties of these Mg films on the si(111) 7$\times$7 surface at various coverages.