• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1708-1716
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• 2016

Glucose dehydrogenase (GDH) is an oxidoreductase enzyme and is used as a biocatalyst to regenerate NAD(P)H in reductase-mediated chiral synthesis reactions. In this study, the glucose 1-dehydrogenase B gene (gdhB) was cloned from Bacillus thuringiensis subsp. kurstaki, and wild-type (GDH-BT^WT) and His-tagged (GDH-BT^N-His, GDH-BT^C-His) enzymes were produced in Escherichia coli BL21 (DE3). All enzymes were produced in the soluble forms from E. coli. GDH-BT^WT and GDH-BT^N-His showed high specific enzymatic activities of 6.6 U/mg and 5.5 U/mg, respectively, whereas GDH-BT^C-His showed a very low specific enzymatic activity of 0.020 U/mg. These results suggest that the intact C-terminal carboxyl group is important for GDH-BT activity. GDH-BT^WT was stable up to 65℃, whereas GDH-BT^N-His and GDH-BT^C-His were stable up to 45℃. Gel permeation chromatography showed that GDH-BT^WT is a dimer, whereas GDH-BT^N-His and GDH-BT^C-His are monomeric. These results suggest that the intact N- and C-termini are required for GDH-BT to maintain thermostability and to form its dimer structure. The homology model of the GDH-BT^WT single subunit was constructed based on the crystal structure of Bacillus megaterium GDH (PDB ID 3AY6), showing that GDH-BT^WT has a Rossmann fold structure with its N- and C-termini located on the subunit surface, which suggests that His-tagging affected the native dimer structure. GDH-BT^WT and GDH-BT^N-His regenerated NADPH in a yeast reductase-mediated chiral synthesis reaction, suggesting that these enzymes can be used as catalysts in fine-chemical and pharmaceutical industries.

• Membrane Journal
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• v.9 no.3
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• pp.157-162
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• 1999

In the crosslining reaction of poly(vinyl alcohoJ)(PVA) with sulfur-succinic acid which had been established in our previous work, reaction temperature, 15$0^{\circ}C$, was so high to collapse the pore struc¬tures in support membrane for the preparation of composite membrane. Therefore, the efforts have been focused on lowering of the reaction temperature to 100$^{\circ}$C by using a catalysis, HC!. The newly established crosslinking reaction was characterized through the analysis of the chemical and thermal properties. From these results, the optimum conditions for the membrane preparation couId be drawn as followings : (i) reac¬tion temperature, 100 $^{\circ}C$,(ii) reaction time, 90 min, (iii) the concentration of the catalysis (HCD, 1.5%. Com¬posite membranes were fabricated by coating a casting solution containing PYA, sulfur-succinic acid and HCl on a support membrane followed by crosslinking it at 10$0^{\circ}C$. The resulting membranes were applied to the pervaporation separation of methyl-tert-butyl ether(MTBE)/methanol (MeOH) mixtures at 30, 40, and 5O$^{\circ}C$. The flux of 5.09 g/$m^2$hr at 5O$^{\circ}C$ and the highest separation factor of 1622 were obtained, respectively.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.114-119
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• 1984

In order to improve the quality of silages made of rice straw, clover and sweet potato stalk, crushed fresh sweet potatoes(CFSP) were added at various levels to each silage. When the fermentation was completed, the chemical composition, pH and main organic acid contents of each silage were analized. The results obtained were summarized. 1. The moisture content of sweet potato stalk silage was highest among all silages tested. The clover silage showed the highest value in crude protein content. On the other hand, the rice straw silages were high in NFE and crude fiber contents. When the level of CFSP increased, the NFE contents tended to increase and crude fiber decrease. 2. The content of total organic was highest in clover silage. However, the percentage of lactic acid in total acid content was highest in sweet potato silage. The percentage of lactic ac id in total acid content was increased in paralled with the levels of CFSP. 3. The sweet potato stalk silages showed the lowest pH value (4.10-4.20). The highest pH values were 4.75-5.22 in rice straw silage. The addition of CFSP tended to lower the pH. 4. It appears the quality of clover and rice straw silages can be imp roved by adding CFSP at 5 and 10% levels, respectively, on fresh weight basis. The addition of CFSP to the sweet potato stalk silage, however, was not effective in this experiment.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.87-94
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• 2009

Surfactant-enhanced air sparging (SEAS) was developed to suppress the surface tension of groundwater prior to air sparging resulting in higher air saturation and larger contact area between NAPL and gas during air sparging. Larger contacting interface between NAPL and gas means faster mass transfer of contaminants from NAPL to gas phase. This new technique, however, is limited to relatively volatile contaminants because vaporization is its basic mechanism of mass transfer. In this study, SEAS was tested at an elevated temperature for a semi-volatile n-decane, which is expected not to be a good candidate of SEAS application due to its low vapor pressure at ambient temperature. Three sparging experiments were conducted using 1-dimensional column (5 cm id, 80 cm length) packed with sand; (1) ambient temperature ($23^{\circ}C$), column saturated with distilled water, (2) SEAS at ambient temperature ($23^{\circ}C$), for n-decane contaminated sand, (3) SEAS at elevated temperature ($73^{\circ}C$), for n-decane contaminated sand. Higher air saturation was achieved by SEAS compared to that by air sparging without surfactant application. The n-decane removal efficiency of SEAS at elevated temperature was significantly higher(> 10 times) than that of ambient SEAS. The n-decane concentrations in the gas effluent from column during SEAS at $73^{\circ}C$ are found to be 10 times of those measured at ambient temperature. Thus, SEAS technique can be applied for removal of semi-volatile contaminants provided that an appropriate technique for elevating aquifer temperature is available.

• Journal of the Korean Society of Costume
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• v.22
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• pp.159-176
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• 1994

This study's purpose is to find the ancient costume of the folk song's words on Dunhuang manuscripts in the background wass-carvings sculptures and several art works. Dunhuang had played the part of major route between ancient China and Europe. It is located on kam-suksong the west of China. 1. In the aspect of costume arrangement hair Styling is represented by Naegagyo, Wangyesa, Kyongburak, Bonkwyun, Pogurak, Chonsonja, Namgaja, Tongson-ga, Ojesa, Chanboja in Dunhuang manuscripts. tugue is sim-ilar to Sabyokkwanja in Naegagyo as of that time these kinds of Kwan-ja was very popular. It was told that emperor's wife concubine and maid of honor would wear kwnaja favorably. And the kinds of Tugeu is PuyongKwyunkye, Aangunkye, Chunkye from Kyuwanjon except Sangunkye, Ounkye in Dunhuangsa. 2. Jangdaegy is guoted from Kyuw-anjon -A series of the chinese history book-tells us about women's make-up . The narmes of make-up are Hongjang Unjan--g, Yiljang chwejang, Tam-ajang Murgjang, Sanagjang, Light-make up are referred in Naegagyo is included as packjang Besides we can find other make-up skills Huphwaro and Rujang from the Kaewonch onbon-wisa which was Yangkwibi's episodes. We can find the a corpus of song's words about cosmetic custom in Kor-ea. Which is 'Haecho' folk song in the souther-en costal regions 'Jinggum' folk song in Kim-hae regions and so on.... It's words is similar to Dunhuangsa in China. 3. Bichun inherited to China with India Bud-dism art in the middle of Dunhuang wall-pain-tings is one of the important Buddist saint. Sometimes it is painted with Giakchun Its arms of fly-dnacing in heaven with colored belt on body has almost the form of play on the musical instrument, We can see seasily the form in the painting of Buddist ser-mon. It was progressed and changed with the background of chinese traditional culture. When Dang's period came the color was chan-ged lighting dark blue has rhythmical and viv-id power of life. 4. Among the corpus of song's words which express the singers' system and rites of their tradition or habits. Dunhuang manuscripts des-cribes on behalf of the folk song's words in tra-ditional costume. This is following: (1) Naegagyo o sabyokwanja o Chyrasam o Rashang (2) Wangyesa o Sokryugun o Costume for fisher man (3) Bungajang of the chanboja o Ajang (4) Pongkwyun o Chongui (5) Tongsongs o Junofore (6) Namgaja o thin-Rasam (7) Yuchungnang o Hongsam o Sokryugun : The color of red costume (8) Kyongburak o Hongrasam o Sokryugun : Costume for charming woman Therefore traditional costume could be extracted according to the Dunhuang folk song's words out of culture such as learning rit-es three-obedience four-virtues and in-struction. As the same time it reflects ancient China's characteristics directly. I would endeavor to development for the history of the costume furher creative design and participat-ed in research activity with concerns forward continuously.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.69-76
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• 2017

In the Korea, 80 percent of livestock manure were converted into compost and used as organic fertilizers. The livestock manure compost has two types of powder and pellet type (ID= 5~10 mm). The aim of this study was to investigate the properties of two types of cow manure compost pellet (cylinder and sphere type). Nitrogen concentrations of cylinder type and sphere type of compost pellets were 1.23 and 1.24%, respectively. There were similar with nitrogen concentration of cylinder and sphere types of compost pellets. As a result of analyzing the effect of granulation processing, it was found that the moisture content of the raw material was the most influential factor in the granulation processing in both of the processing types of the screw pressing method and the rotating cylinder method. When the cylinder and sphere types of compost pellets were dry to 20% of moisture content, the specific gravities of these compost pellets were 1.38 and 1.13, respectively. The compressive strength of cylinder type pellet and sphere type pellet were 27.6 and $11.3kg/cm^2$, respectively.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.267-272
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• 2010

The present study was to investigate the source of contamination during semen processing for in vitro uses. In the present study, frozen semen was prepared from liquid semen in our laboratory for in vitro fertilization (IVF) experiments due to lack of fresh semen. Antibiotics were added in the frozen semen extender (kanamycin and gentamicin) and in vitro culture (IVC) medium (gentamicin) for further inhibiting growth of microorganisms. Nevertheless, proliferations of microorganisms were observed in IVC culture drop during culturing of IVF embryos using frozen semen. Randomly 3 samples were taken from the liquid semen, frozen semen and egg yolk. Contaminated IVC medium, frozen-thawed semen, liquid semen and egg yolk were cultured in de Man, Rogosa and Sharpe (MRS) agar medium. Whitish colonies were detected in contaminated IVC drop, frozen-thawed semen samples and egg yolk but no colonies were formed in liquid semen samples. Gram-negative and rod-shaped identical bacteria were found in both frozen-thawed semen sample and contaminated IVC drop and egg yolk samples. Enterobacter cloacae were confirmed by API 20E kit according to manufacturer's instruction with identification value (% ID) 94.3% and T index 0.88. Antibiotic susceptibility tests were done according to Clinical and Laboratory Standards Institute (CLSI) by using ampicillin, amikacin, cephalothin, gentamicin, kanamycin, tetracycline, oxytetracycline, sulfamethoxazole trimethoprim, norfloxacin and ciprofloxacin test. Among them Enterobacter cloacae were resistant to ampicillin, amikacin, cephalothin, gentamicin, kanamycin but susceptible to tetracycline, oxytetracycline, sulfamethoxazole trimethoprim, norfloxacin and ciprofloxacin. From these findings it could be suggested that this contamination sources might be from egg yolk.

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.551-563
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• 2020

The purpose of this study was to identify the characteristics of health-related indicators according to the participation of swimming program by adults with intellectual disabilities(ID). To this end, 20 adults with IDs, aged 20-39 living in Busna, were selected. Participants divided into two groups: swimming program participation(n=10) and non-participation(n=10). Data were collected by measuring the subjects health-related physical fitness, stress hormones, and immune function and data analysis was conducted using SPSS 18.0, paired t-test, independent t-test and two-way ANOVA. As a result, muscle strength(p<.001), muscular endurance(p<.001), flexibility(p<.001), cardiovascular endurance(p<.01) improvement of exercise group significantly but there was no significant difference in the control group. The stress hormone cortisol(p<.01) was significantly decreased in the exercise group and there was no significant difference in the control group. The immunoglobulins, IgA(p<.05), IgG(p<.001), IgM(p<.05) were significantly increased in the exercise group, but not significantly different in the control group. Therefore, regular swimming program can be said to be a very effective exercise program for improving the physical fitness of adults with IDs, and it is thought that it can reduce stress and help improve immune function. This suggests the need for active physical activity program development and intervention to maintain the health of adults with IDs and prevent chronic diseases.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.342-350
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• 1988

An experimental investigation is made to determine the mechanism of the aquation of $[Co(en)_2Cl_2]^+$ in $Hg^{2+}$ aqueous solution. The progress of reaction is followed UV/vis-spectrophotometrically by a measurment of the absorbance at a specific wavelength of Co(III) complex as a function of time. The aquation of cis-$[Co(en)_2Cl_2]^+$ and trans-$[Co(en)_2Cl_2]^+$ has been found to be first order and second order with respect to the concentration of $Hg^{2+}$ catalyst, respectively. It has been found that the reaction rate for aquation of the trans-form is faster than that of cis-form, and that the product of either cis-form or trans-form is always in the mixture ratio of 97 % to 3 %. Plausible reaction mechanism is proposed for the reaction system on the basis of kinetic data and activation parameters. Theoretical rate equation derived from the proposed mechanism is consistent with the observed one.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1148-1157
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• 2006

A hyperthermophilic bacterium Thernotoga maritima produced thermostable ${\beta}-glucosidase$. The gene encoding ${\beta}-glucosidase$ from T. maritima MSB8 was cloned and expressed in Escherichia coli. The en-zyme (BgIB) hydrolyzed ${\beta}-glucosidase$ linkages between glucose and alkyl, aryl of saccharide groups such as salicin, arbutin, and $_pNPG$. The insert DNA contained ORF with 2,166 bp encodes a 721 amino acids (calculated molecular mass of 80,964 and pl of 4.93). The amino a.id sequence of BglB showed the similarity to family 3 glycosyl hydrolases. The molecular weight of the enzyme was estimated to be approximately 81kDa by MUG-nondenaturing PAGE (4-methylumbelliferyl 13-D-glucoside-nondenaturing polyacrylamide gel electophoresis) and SDS-PACE. The ${\beta}-glucosidase$ exhibited maximal activity at pH 7.0 and $80^{\circ}C$. By exchanging two possible residues (Glu-232 and Asp-242) to Ala by site-directed mutagenesis method, it was found that these were essential for enzymatic activity.