• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.254-262
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• 1980

A series of experiment were carried out to separate the factor accelerating the lysis of cell wall of $Saccharomyces\;sak{\acute{e}}$ from the preparation of crude zymolyase obtained from Arthrobacter luteus. An attempt was also made to purify the enzyme which is essential for the study on the separation of the factor. The results are summarized as follows: 1. Crude zymolyase was fractionated 5 peaks $(A{\sim}E)$ containing three peaks $(A{\sim}C)$ passed through the column by the chromatography on Biogel CM-30. 2. Among the five peaks, peak E (protease fraction) was found to contain the factor accelerating the lytic activity of the zymolyase. 3. L-c fraction purified in almost free form from the nonlytic ${\beta}-1$, 3-glucanase, protease and inert protein by the affinity adsorption chromatography with Sephadex G-75 gel was obtained from zymolyase fraction (peak D). When it was subjected to polyacrylamide gel disc electrophoresis, only one clear protein band was observed at pH 4. 5, but still detected two or more band at pH 8. 3.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.178-184
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• 1971

Samples of refined soybean oil were irradiated with lights from a 20-watt incandescent tungsten lamp, a 20-watt fluorescent daylight type lamp, a 20-watt low-pressure mercury vapor germicidal lamp, and direct sunlight for an experimental period of 147 days. Some samples were stored in a dark room throughout the period as a control. The peroxide values of all samples were measured every week. The induction period of the samples was arbitrarily taken as the time required for the samples to reach a peroxide value of 15. The induction period of the control was estimated at 198 days. Those of the samples irradiated with the incandescent light, the fluorescent light, the ultraviolet light, and the sunlight were estimated at 196, 119, 52 and 6 days, respectively. The sunlight showed by far the strongest prooxidant activity whereas the incandescent light showed the weakest but distinct prooxidant activity. The small temperature differences observed among the various samples throughout the experimental period did not seem to affect the oxidation rates of the irradiated samples in any significant way.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.791-799
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• 1996

The purpose of this study was to compare the shear bond strength of adhesion bridge by various resin cements. One hundred and foully 1st premolars were used. The teeth were cut below 2mm from CEJ and the coronal portions were used. The coronal portions were embeded with the acrylic resin and trimmed with sic paper until the flat plane with ${\phi}$ 4mm above acrylic resin sticks in height 5mm were casted with nonprecious metal and the using surfaces were treated with sic paper from #200 to #1200 and polished with alminum oxide paste. And then, the using surfaces were sandblasted and treated with the electrochemical etching. The teeth were divided into three groups of fourty two each. In group I, teeth and specimens were cemented with Panavia 21 In group II, teeth and specimens were cemented with Superbond In group I, teeth and specimens were cemented with All-Bond & composite resin cement Each group was subdivided into three subgroups according to the storage period ; one-day storage, fifteen-day storage, and thirty-day storage. The special jig was made. Then, the specimen and jig were mounted to Instron Universal Testing Machine and the failure were measured. The results were as follows. 1. There was statisfically significant difference between the failure loads of group I and group II and III after one day storage(P<0.01), 2. There was statisfically significant difference between the failure loads of group II and group I and III and between group I and group III at fifteen day storage(P<0.01). 3. There was statisfically significant difference between the failure loads of group I and II and group III after thirty day storage(P<0.01). 4. There was statisfically significant difference between the failure loads of one day storage and fifteen and thirty days storages in group III (P<0.01).

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.558-567
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• 1989

The synthesis of methanol from carbon dioxide and hydrogen was studied for various compositions of Cu/ZnO catalyst system. Effect of the composition ratio of CuO and ZnO on the catalytic activity in the above reaction and the relationship between the activity and the characteristics of the catalysts were explained from the result of surface area measurements, SEM, XRD, and XPS. The major products of the reaction were methanol and carbon monoxide. The selectivity to methanol increased with increase of the copper oxide content in the catalyst up to CuO: ZnO = 30:70 weight ratio, and decreased rapidly when the content is above 70%. SEM and BET measurements, indicate that this point corresponds to the increasing point of the catalyst crystallite size and the decreasing point of the surface area. As to the Cu/Cu + Zn atomic ratio, the surface concentration of copper measured by XPS decreased remarkably when the copper oxide content in catalyst was higher than 50%. All the unreduced catalysts had almost same binding energy of Cu(2P3) level, but the binding energy for $Cu(2P^3)$ level of reduced catalysts was lowered than that of calcined catalysts. The surface copper species which was in the maximum amount when the CuO:ZnO composition in the catalyst was 30:70, existed as zero valent copper. This result agreed with the experimental result that the highest rate of methanol formation was observed when the CuO content in the catalyst was 30%. It was postulated that these reduced catalysts performed with a relatively strong basicity because the formation rate of acetone was higher than that of propylene in isopropanol decomposition as measured in a pulse type reactor.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.135-140
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• 2000

Development and reproduction of the cotton caterpillar, Palpita indica, were investigatedunder different temperatures (15 .O, 17.5, 20.0, 22.5, 25 .O, 27.5, 30.0, 32.5, and 35 .O$^{\circ}$C). Duration fromegg to pre-adult of the cotton caterpillar were ranged from 68.6 days at 175$^{\circ}$C to 19.7 days at 35.0% (3.5times shorter growth period compared with that at 17S$^{\circ}$C). At 15.0$^{\circ}$C, cotton caterpillar eggs developedto the last larval instar but were not able to go through the pupal stage. The lower developmentalthreshold temperatures and degree-days of egg, larva, pupa, and complete development were 13.4, 10.6,11.6, and 11.5"C and 55.3,251.5, 138.3, and 479.8 degree days, respectively. The hatching, pupation andemergence rates were higher at 25.0eC and 27.5"C compared with other temperatures. The survival ratefrom the hatched larva to adult was the highest at 27.5"C. The preoviposition and the adult longevity were11.5 and 30.6 days at 17.5"C and 1.5 and 9.2 days at 35.0$^{\circ}$C, respectively. The mean fecundity perfemales was greater at 25.0$^{\circ}$C and 27.5"C compared with other temperatures. Mean generation time indays (T) was shorter on higher temperature. Net reproductive rate per generation (R,) was the lowest atthe highest temperature as well as at the lowest, and it was 199.1 which was the highest at 27.5"C. Theintrinsic rate of natural increase (r,) was highest at 30.0$^{\circ}$C as 0.148. As a result, optimum ranges oftemperature for P. indica growth were between 25.0-32.5"C .emperature for P. indica growth were between 25.0-32.5"C .t;C .

• Radiation Oncology Journal
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• v.22 no.2
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• pp.145-154
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• 2004

Purpose : To examine whether a synthetic bile acid derivatives (HS-1200) sensitizes the radiation-induced apoptosis in human breast cancer cells (MCF-7) and to investigate the underlying mechanism. Materials and Methods : Human breast cancer cells (MCF-7) in exponential growth phase were treated with HS-1200 for 24 hours at 37$^{\circ}C$ with 5$\%$ CO$_{2}$ in air atmosphere. After removal of HS-1200, cells were irradiated with 2$\~$8 Gy X-ray, and then cultured Ii drug-free media for 24-96 hours. The effect of radiation on the clonogenicity of MCF-7 cells was determined with clonogenic cell survival assay with 16$\mu$M of HS-1200. The induction of apoptosis was determined using agarose gel electrophoresis and Hoechst staining. The expression level of apoptosis-related molecules, such as PARP, Bax, Bcl-2, Bak and AIF, were assayed by Western blotting analysis with 40$\mu$M of HS-1200 combined with 8 Gy irradiation. To examine the cellular location of cytochrome c, bax and AIF immunofluorescent stainings were undertaken. Results : Treatment of MCF-7 cells with 40$\mu$M of HS-1200 combined with 8 Gy irradiation showed several changes associated with enhanced apoptosis by agarose gel electrophoresis and Hoechst staining. HS-1200 combined with 8 Gy irradiation treatment also enhanced production of PARP cleavage products and increased Bax/Bcl-2 ratio by Western blotting. Loss of mitochondrial membrane potential ($\Delta$$\psi$$_{m}$) and increased cytochrome c staining indicated that cytochrome c had been released from the mitochondria in HS-1200 treated cells. Conclusion : We demonstrated that combination treatment with a synthetic chenodeoxycholic acid derivative HS-1200 and irradiation enhanced radiation-induced apoptosis of human breast cancer cells (MCF-7). We suggest that the increased Bax/Bcl-2 ratio In HS-1200 co-treatment group underlies the increased radio sensitivity of MCF-7 cells. Further futures studies are remained elusive.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.69-78
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• 1996

This study was done to investigate the enzyme-histochemical localization and characteristics of alkaline and acid phosphatase related with metabolism in sparganum and adult of Spirometrn erinacei. By the enzyme-histochemical assay, the alkaline and acid phosphatases were localized in the tegument and subtegumental musculature of sparganum and adult, but not in the parenchyma. The activities of alkaline phosphatase were stronger in the tegument than in the subtegumental musculature, and activities of acid phosphatase were stronger in the tegument of adults than those of sparganum. The 2 isozymes of alkaline and acid phosphatases were separated from s-sparganum (from snake) and r-sparganum (from experimentaly infected rats) respectively but 4 isozymes of Alp and 3 isoxymes of Acp were separated from adult worms by electrophoresis. In isogyme Alp, the 661)a was the common isozyme, but 130 kDa isozyme of Acp was the common isozyme in spargana and adult worms. By isoelectrofocusing, 4 isozymes (PI 7.9, 7.7, 6.5 and 6.3) and 2 isozymes (PI 7.9 and 7.7) of alkaline phosphatase were separated from adults and spargana respectively. In the stability against heat, activity of alkaline phosphatase was denatured perfectly after heating at 90℃ for 40 seconds. The optimum pH and temperature for activity of alkaline phosphatase were about pH 10 and 50℃, respectively. The maximum activity (unit) of alkaline phosphatase was 22.0 in s- sparganum,25.0 in r-sparganum and 215.0 in adult worms, so that the maximum activity was revealed higher in adults than spargana. As the result from above, we observed that alkaline and acid phosphatases were functioned mainly in the tegument and subtegumental musculature , and the isoxymes of phosphatase were activated differently according to habitat of the parasites. The spargana and adult worms carry out the pafasitism by adapting thenlselves to parasitic circumstance loth these emxymes.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.59-68
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• 1996

This study investigated the enzyme histochemical localization and characteristics of lactate (LDH) and malate dehydrogenase (MDH) related with the oxidation-reduction metabolism in the sparganum and adult of 5. erinacei. By enzyme histochemical assay, activity of LDH was strong in the tegument and subtegumental muscle layers of the adult and sparganum. Activity of MDH was strong in the tegument of the sparganum and subtegumental muscle layers of the adult. However it was weak in the tegument of the adult. By electrophoresis, 45 kDa band was major and common in LDH of adults and spargana. The 150 kDa molecule was the major and common band in MDH of adults and r -spargana (from experimentally infected rats) . By isoelectrofocusing, isoelectric points (Pl) or 4 MDH isogyme from adult worm were 6.0.6.5, 6.7 and 7.1, respectively. Pl 6.0 was the major band. The active range of pH for MDH was about pH 6-8 and the optimum pH was pH 7 The effective temperature on the MDH was about $30^{\circ}C$∼$50^{\circ}C$ and the optimum temperature was about 40℃ in spargana md adult worm. In the stability against heat, when MDH was heated at 85℃ for 10 seconds, the activity was denatured perfectly. Maximum activity or MDH was 19.4 unit in the s-sparganum (from snakes), 24.5 unit in the r-sparganum (from rats) and 108.0 unit in the adult worm. The maximum activity was higher in adults than in spargana. The present result showed us that the nutrients absorbed through the tegument were transferred into inner tissues and were utilized as the source of metabolism. According to the habitat of the parasite, the isozymes of LDH and MDH are activated differently, and by this different activation the sparganum and adult can adapt themselves to parasitic circumstances.

• Journal of the Korean Magnetics Society
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• v.17 no.1
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• pp.18-21
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• 2007

The hexagonal $HoMn_{1-x}-Fe_xO_3$(x=0.00, 0.05) thin films were prepared using pulsed laser deposition(PLD) method on $Pt/Ti/SiO_2/Si$ substrate. The microstructure and magnetic properties have been studied by x-ray diffraction(XRD), atomic force microscopy (AFH), scanning electron microscope(SEM:), x-ray photoelectron spectroscopy(XPS), and conversion electron $M\"{o}ssbauer$ spectroscopy(CEMS). From the analysis of the x-ray diffraction patterns, the crystal structure for all films was found to be a hexagonal($P6_3cm$), which was preferentially grown along(110) direction. The lattice constant $c_0$ of the film with x=0.05 was close to that of single crystal, whereas lattice constant $a_0$ with respect to single crystal shows a slight decrease. This difference of lattice parameters between film and single crystal was caused by the lattice mismatch between the film and $Pt/Ti/SiO_2/Si$ substrate. Conversion electron $M\"{o}ssbauer$ spectrum of $HoMn_{0.95}Fe_{0.05}O_3$ thin film shows an asymmetry doublet absorption ratio at room temperature, which is due to the oriented direction of crystallographic domains. This is corresponding with analysis of x-ray diffraction. The quadrupole splitting(${\Delta}E_Q$) at room temperature is found to be $1.62{\pm}0.01mm/s$. This large ${\Delta}E_Q$ was caused by asymmetry environment surrounding Fe ion.

• Sijohaknonchong
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• v.30
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• pp.109-146
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• 2009

It is academically recognized that Jeong Wan-Young's sijo better represent Oriental ideas. The purpose of this study is to investigate Taoistic characteristics of Jeong Wan-Young's sijo. This is an effort to succeed and further deepen and extend previous relevant researches. For the purpose, this researcher categorized the poet's sijo in accordance with such characteristics as above mentioned. Findings of the study can be summarized as below. Pieces of Jeong Wan-Young's sijo which are based on Taoistic ideas are largely classified into three groups. First, some pieces of Jeong Wan-Young's sijo represents an orientation of return to hometown which is brought by the sense of loss. His sense of loss is attributed to the facts that his home is not what it was any longer and that he can't return to the old home. To overcome the sense, nevertheless, the poet is dreaming of return to home. The home found in Jeong Wan Young's sijo is something fundamental and original that he purposedly provided against the feeling of loss. It complies with the concept of 'Bokgwigigen(復歸基根)‘ a pursuit of Taoism. Second, other pieces of Jeong Wan-Young's sijo are seeking purity to retrieve childish innocence. Their subjects include the season of spring, dreams of childhood and longing for mother all of which represent the poet's strong desire for such retrieval as above mentioned. It may be said that pursued by that pieces are 'Purity, Feebleness and Smoothness' that are sought by Taoism. Third, other pieces of Jeong Wan-Young's sijo are considering human as a part of nature and seeking human life in harmony with nature. In other words, they are seeking union between human and nature which means going beyond discrimination between self and external objects, that is, 'Mulayangmang(物我兩忘)'. This may refer to return to nature which is the ultimate destination of Taoism.