• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.1-7
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• 1998

For the purpose of finding new cathode materials for medium-temperature $(700\~800^{\circ}C)$ solid oxide fuel cells, $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3,\;(x=0.0\~0.5)$ are prepared, and their thermal stability and conductivity characteristics are investigated. Also, the cathodic activities are measured after the cathode layer being attached on CGO (cerium-gadolinium oxide) electrolyte disk. The X-ray analyses indicate that the materials prepared by calcining the citrate-gels at $800^{\circ}C$ have the orthorhombic perovskite structure without discernible impurities. The thermal stability of the undoped Co perovskite is so poor that it is decomposed to the individual binary oxide even at $1300^{\circ}C$. But the partially Fe-doped cobaltates exhibit a better thermal stability to retain their structural integrity up to $1400^{\circ}C$. The observation whereby both the undoped and Fe-doped cobaltates melt at ca. $1300^{\circ}C$ leads us to perform the electrode adhesion at <$1300^{\circ}C$. The cathodic activity of $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3,\;(x=0.0\~0.5)$, electrodes is superior to $La_{0.9}Sr_{0.1}MnO_3$, among the samples of $x=0.0\~0.5$, the x=0.2 cathode shows the best activity for the oxygen reduction reaction. It is likely that the Fe-doping provides a better thermal stability to the materials but in turn imparts an inferior cathodic activity, such that the optimum trade-off is made at x=0.2 between the two factors. The total electrical conductivity and ion conductivity of $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3$, are measured to be 51 S/cm and $6.0\times10^{-4}S/cm\;at\;800^{\circ}C$, respectively. The conductivity values illustrate that the materials are a mixed conductor and the reaction sites can be expanded to the overall electrode surface, thereby providing a better cathodic activity than $La_{0.9}Sr_{0.1}MnO_3$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1164-1170
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• 2017

Protaetia brevitarsis larvae (PBL) has recently been registered as a temporary food in Korea, and this study evaluated the application potential of PBL proteins as health functional food materials. Protein hydrolysates were prepared from PBL powder by enzymatic hydrolysis using five different proteases (alcalase, bromelain, flavourzyme, neutrase, and papain), and based on the results from the peptide content and SDS-PAGE analyses, PBL treated with alcalase or flavourzyme showed a high degree of hydrolysis (HD) value, whereas the HD value of those treated with neutrase, bromelain, or papain was minimal. The protein hydrolysates showing a high HD value were separated further into the fractions of >3 kDa and <3 kDa by a centrifugal filter system and then lyophilized, and according to the $RC_{50}$ values of the protein hydrolysates (<3 kDa) obtained from three different antioxidant analyses; the alcalase hydrolysates showed the highest antioxidant activity. Therefore, the alcalase hydrolysates were tested further for their inhibitory effects on the peroxidation of linoleic acid by measuring the thiobarbituric acid values. The results showed that the peroxidation of untreated linoleic acid increased dramatically during 6 days of incubation, but a pretreatment with the hydrolysates ($100{\sim}800{\mu}g/mL$) significantly inhibited the linoleic acid peroxidation in a dose-dependent manner for 6 days. Our current studies are focused on the identification of active peptide sequences from alcalase hydrolysates.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.1
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• pp.54-59
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• 1999

This study was based on a series of 164 patients with zygomatic bone fracture treated at Department of Oral and Maxillofacial Surgery of Chonnam University Hospital from January 1992 to December 1996. The male-to-female ratio was 7:1. Their ages ranged from 8 to 78 years, with a median age of 35.6 years. The age frequency was highest in the second decade (30.5%), and third decade (23.8%), fifth decade (16.5%) in orders. The monthly distrbution of incidence showed October to be the month in which the greatest percentage occured (14.0%). The major cause of zygomatic bone fracture was alleged traffic accidents (53.7%). The incidence of concomitant facial bone fractures was 69,5%, and maxilla fracture (52.4%) was most frequently combined. The admission route was through emergency room (72.3%) and through outpatient department (26.8%). The incidence of associated injuries was 37.2%. The intraoral approach was the major method of treatment in zygomatic bone fracture (57.1%). The most frequent type of zygoma fracture was class IV (33.5%), and class III (25.6%) was next in order of frequency. Complications were enophthalmos (7.3%), facial asymmetry (6.7%), paresthesia (6.1%), and diplopia (2.4%) These results suggest that correct diagnosis and treatment of severity of fracture, concomitant fracture, and associated injuries are necessary, and co-operative treatment with medical department should be performed to reduce postoperative complication.

• Journal of Korean Home Economics Education Association
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• v.29 no.1
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• pp.71-92
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• 2017

The purpose of the present study is to investigate the experiences of original family and social relationships in single women. Semi-structured in-depth interviews were arranged with 18 single women who met the criteria for the present research purpose. We considered only those responses of the interviewees that are directly related to their experiences of original family and social relationships, where the collected data were analyzed in three steps by methods of thematic analysis. As a result of the analysis, the experiences of original family and social relationships in single women could be grouped into six main clusters of themes which may be labeled as (1) themes centered on 'Family attachment', (2) themes centered on 'Special People' and (3) themes centered on 'Estrange relative relationship'. (4) themes centered on 'Small social life', (5) themes centered on 'Absence of a social relationshipship', (6) themes centered on 'Drive for freedom'. Among the first category of themes of 'Family attachment', we have found three sub-themes such as 'Adult Baby under parents' care', 'Confirm of single life', 'Intricate family relations'. As for the second category of themes 'Special People', three sub-themes have been found including 'I Only Love Mom.', 'Sister friend', 'My lovely nephew or niece'. And for the third category of only one theme 'Estranged relative relationship'. And for the fourth category of themes 'Small social life', there were found four sub-themes which include 'Relationship at work', 'Chat with friends', 'Keep oneself aloof from the opposite sex', 'Singles gather together'. And for the fifth category of themes 'Absence of a social relationshipship', there were found three sub-themes which include 'Alone than meeting', 'Lazism', 'Tight daily lives'. And for the final category of themes 'Drive for freedom', there were found two sub-themes which include 'Caution for attachment', 'Caution for entanglement'. In all, there are sixteen sub-themes to consider. On the basis of these results, we presented some conclusions on the experiences of original family and social relationships in single women. We also presented some implications of these results on population education and future research.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.167-175
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• 2005

Houttuynia cordata THNUB (He; Uh-Sung-Cho) is a medicinal plant which has been widely used as a component of blood-building decoctions. This study was performed to investigate the immunomodulative effect of He in mice. In vitro experiment, the mice splenocytes proliferation and three kinds of cytokines (IL-1$\beta$, IL-6, TNF- $\alpha$) production by mice peritoneal macrophages cultured with six (methanol, hexane, chloroform, ethylacetate, butanol and water) fractions of He were used to indicate the immunomodulative effect. Ex vivo experiment, the different concentrations of He water extract was orally administrated every other day for two weeks. The production of cytokines IL-1$\beta$, IL-6, TNF- $\alpha$) secreted by activated macrophages and the mice splenocytes proliferation were used as an index for the immunocompetence. The supplementation of all six fractions of He enhanced the splenocytes proliferation at the level of 6.58$\pm$1.23∼47.82$\pm$5.48 compared to that of control in the range of 1∼50 $\mu\textrm{g}$/mL. IL-1$\beta$ production was significantly increased with the supplementation of chloroform and water extract of He. Higher level of IL-6 production was detected by the supplementation of ethylacetate, butanol and water extract. TNF - $\alpha$ production was enhanced by the supplementation of all six fractions of He. From the ex vivo study, the highest proliferation of splenocytes was seen from the mice orally administrated with the He water extract at the concentration of 500 mg/kg bw In case of cytokines production, IL-1$\beta$, IL-6, and TNF- $\alpha$ release by activated peritoneal macrophages were augmented by the oral administration of He water extract. These results indicated that He may enhance the immune function by regulating the splenocytes proliferation and cytokines production capacity in mice.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.439-443
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• 2010

The purpose of this study was to prevent excessive use of fluorine toothpaste. To comparatively evaluate the amount used of the fluorine toothpaste in children from 3 to 6 years old, the toothpaste amount was compared according to toothbrush size and toothpaste squeezing method targeting 84 children in 5 child care centers where were located in Hongseong-gun, Chungnam. The toothpaste amount was compared with a method of squeezing to pea-size and a method of smear on toothbrush, targeting 141 students for the Dept. of Dental Hygiene, who are actually carrying out oral health education to targeting children. The statistical analysis was used SPSS 14.0 K for Windows program(Copyright(c) SPSS Inc.). The following results were obtained. 1. The amount of fluorine toothpaste squeezed on toothbrush for children was 0.29 g. The amount of fluorine toothpaste squeezed on toothbrush for adults was 0.34 g. It was surveyed to use the less amount of toothpaste when squeezing to smaller toothbrush (p<0.05). 2. The amount that children aged 3-6 squeezed as the method of squeezing commonly at ordinary times was 0.31g. The amount that was squeezing to pea-size was 0.21 g. The amount that was squeezed by using smear method was measured to be 0.26g. Less amount of fluorine toothpaste was used with the method of squeezing to pea-size and smear method rather than a method of squeezing commonly at ordinary times(p<0.05). 3. As a result of surveying the students of the department of dental hygiene, the amount of having squeezed to pea- size was 0.23 g. It was surveyed to be 0.15 g when having used the smear method. Thus, it was surveyed to use the less amount of toothpaste when using the smear method(p<0.05). 4. Using smaller toothbrush, the amount used of fluorine toothpaste can be reduced. Both smear method and the method of squeezing to pea-size are available for minimizing careless fluorine intake by less used amount of fluorine toothpaste.

• Investigative Magnetic Resonance Imaging
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• v.7 no.2
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• pp.132-136
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• 2003

Purpose : To evaluate the usefulness of breath-hold T2-weighted MR imaging in patients with myocardial infarction. Materials and Methods : We investigated 11 patients with myocardial infarction who shown delayed enhancement on MR imaging. Infarcted myocardium on T2-weighted MR imaging was classified as high, iso, and low signal area comparing with normal myocardium. The intensity and transmural extent of infracted myocardium was also analyzed. On the basis of clinical information, the stage of infracted myocardium on T2-weighted MR imaging was assessed. Results : It was observed high signal area in 12 segments of 5 patients, low in 12 segments of 6 patients on T2-weighted MR imaging. The high signal intensity of infarcted myocardium was shown as $175{\pm}9\%$ comparing with that of the normal myocardium, low signal intensity as $73{\pm}5\%\;(p\;<\;0.05)$. In the evaluation of transmural extent, the high signal areas on T2-weighted MR imaging were larger than infarct area on delayed enhancement imaging $(100\%\;vs.49\%{\pm}17\%)$, whereas low signal areas on T2-weighted MR imaging correlated. High signal area was visualized on T2-weighted MR imaging within 11 days, whereas low-signal area was seen after 7 months. Conclusion : Breath-hold T2-weighted MR imaging is useful in the evaluation of stage as well as edema and fibrous scar in patients with myocardial infarction.

• Journal of Mushroom
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• v.11 no.3
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• pp.131-136
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• 2013

The effects of fixed and variable relative humidity on fruiting body formation and characters of Pleurotus eryngii were investigated with normal and thinning treatment plots. In fixed relative humidity, as humidity was lower, period of harvest was longer as well as days for pinheading in the both of normal and thinning plots. In the normal plot, qualities of mushroom were 5.5, 5.8, and 6.3 and yield was 98.6 g per bottle for 90% relative humidity, it was best. In the thinning plot, qualities of mushroom were 7.7, 8.4, and 8.5 and yields were 102.1, 105.8, and 116.9 g at 70, 80, and 90% respectively. In variable relative humidity with a thinning plot, the yield of P. eryngii on condition I(>90% for 1 day ${\rightarrow}$ 85% until thinning(for about 11 days) ${\rightarrow}$ 80%) and III(>90% until pin-heading(about for a week) ${\rightarrow}$ 85% until thinning(about for 5 days) ${\rightarrow}$ 80%) were 85.5 and 87.8 g per bottle, and qualities were 7.8 and 8.0 respectively. For long shelf life and a cultural control of bacterial soft rot disease, the condition I will be more largely adopted by mushroom farmers.

• Food Science and Preservation
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• v.24 no.8
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• pp.1168-1179
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• 2017

In this study, we tried to screen the Bacillus strain having safety probability by isolation of strains from traditional fermented food, measurement of probiotic properties, and the fermentative characteristics of Cheonggukjang. We isolated 400 Bacillus-like isolates from traditional fermented foods. Selected strains examined on the prevalent characteristic such as extracellular enzyme and antibacterial activities, and their safety probability was confirmed by biogenic amine productivity, hemolytic, and harmful substances and enzyme productivity. We selected the 5 strains by analysis of biogenic amine, antibacterial and B. cereus toxic associated gene. Five selected strains were examined on cell surface hydrophobicity, and bile and acid tolerance, and we selected the SRCM100730 as the final strain. SRCM100730 was confirmed B. amyloliquefaciens by 16S rRNA sequencing, and named the B. amyloloquefaciens SRCM100730 (KCCM11966P). Finally, we manufactured Cheonggukjang using SRCM100730 for confirmation of fermentation properties. Manufactured Cheonggukjang did not contain B. cereus, and showed that ${\gamma}$-PGA and extracellular enzyme activities were superior to commercial Chunggukjang. Amino nitrogen content was 544.02 mg% and 26 free amino acid were detected, and the bitterness-related amino acid content was lower than commercial Cheonggukjang. Especially, the amount of GABA was 3 fold higher than commercial Cheonggukjang. These results suggest that SRCM100730 have high availability in commercial probiotics market and fermented food industry.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.5
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• pp.365-374
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• 2009

Purpose : This research evaluates the effect of the use of absorbable membrane barrier with deproteinized bovine bone (Bio-$Oss^{(R)}$, Switzerland) on bone healing in surgically created critical-sized defects in rat calvaria. Materials and Methods : Two standardized transosseous circular calvarial defects (5 mm in diameter) are made in each calvarium of 30 rats. These rats are divided into negative control group(n=15), positive control group(n=15) and two experimental groups(n=15). In the negative control group, defects are only filled with blood clots. In the positive control group, defects are filled with autogenous bone obtained from calvarium; in the experimental group 1, defects are filled with deproteinized bovine bone; and in the experimental group 2, defects are filled with deproteinized bovine bone with absorbable membrane. At the postoperative 1 week, 3 weeks. and 6 weeks, clinical. histologic and histomorphometric evaluations of the defects are performed. Results : 1. The grafted bone without membrane in the calvarial bone defect was scattered but, the grafted bone with membrane was stable. 2. $BioMesh^{(R)}$ membrane was absorbed beginning at 3 weeks, and was absorbed considerably at 6 weeks while maintaining the structural form of the membrane. 3. The use of membrane blocked soft tissue invasion. 4. In histomorphometric analysis. it showed the greatest amount of new bone formation in the positive control group. The amount of new bone formation was greater in the experimental group 2 than experimental group 1. At 6 weeks. the amount of new bone formation was greater in the positive control group than experimental group l(p<0.005). Conclusion : These results suggest that membrane increase the stability of grafted bone and protects from soft tissue invasion, and the use of the membrane may promote new bone formation in deproteinized bovine bone graft area.