• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.435-440
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• 2020

Water is a major ingredient and comprises over 98% content of coffee. In this study, coffees prepared with distilled water (L) and waters with medium (M) and high hardness (H) were investigated for organic acid, caffeine, and eugenol contents and analyzed by sensory evaluation. Organic acid content was the highest in H-coffee. The contents of chlorogenic acid and caffeine, the characteristic bitter taste molecules, were the highest in L-coffee. The level of eugenol, one of the representative aroma components, was the lowest in M-coffee but similar between L- and H-coffees. The sensory evaluation test, conducted on a university student group comprising 56 female and 47 male participants, showed that L-coffee was the most preferred (42% or higher), but there was no significant difference in bitterness, acidity, body, and balance. Results suggest that the preference index of coffee taste among university students may be different from that of coffee experts who prefer coffee extracted with water of certain hardness.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.1052-1065
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• 2020

This study analyzed the effects of professional baseball PPL advertising speed on brand awareness, brand attitude, and behavioral intention for professional baseball consumers. The purpose of this study is to present a method that can be used as a variety of marketing utilization strategies of professional baseball teams and parent companies. This study was conducted on 411 professional baseball consumers. For data processing, frequency analysis, reliability analysis, reliability analysis, and multiple regression analysis were performed using SPSS 25.0 Window Version. Then, the average variance extraction index (AVE) and construct validity (CR) were calculated to verify convergent validity and discriminant validity. In addition, confirmatory factor analysis (CFA) was performed using AMOS 25.0. As a result, first, it was found that entertainment, informativeness, and discomfort, which are sub-factors of PPL advertisement speed, have a significant effect on brand recognition. Second, entertainment, information, and discomfort, which are sub-factors of PPL advertising speed, have a significant effect on brand attitude. Third, entertainment, informativeness, and discomfort, which are sub-factors of PPL advertisement speed, have a significant effect on behavioral intention. Fourth, it was found that brand awareness and brand attitude have a significant effect on behavioral intention.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.491-499
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• 2001

Generally, several hydrological characteristics which can be obtained from geographic processing in GIS S/W would be utilized to actual hydrological applications such as landslide stability or drainage analysis. Furthermore, by using practical GIS extension programs, it can be possible that automatic extraction task of those information, which was time-consuming and complex processing, is performed as systematical and automatic processing. In this study, using ArcView GIS S/W and its extensions concerning hydrological processing, some waterflow and surface factors in the area of Yemi sheet scaled 1:50,000 were extracted. Then, assessment of landslide stability, determined by DEM-based variables were carried out in order to investigate practical applicability of extension programs. It is thought that several hydrological factors extracted by this study were significant information to predict field model or hydrological hazardous events. It also reveals that landslide potential is overall stable with stability index mapping and S-A plot, with theoretical basis. This methodology can be applicable to other areas related to hydrological characteristics with measurements in fields.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.539-556
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• 1995

Periodontal therapeutic modalities should be re-establishing and regenerating the periodontal tissue previously lost to the disease. To achieve periodontal regeneration, periodontal ligament cells must selective migrate to the deneded root surface, attached and proliferated it. Local pH concentration is one of the most factors that periodontal regeneration. The aims of this study were to examine on biological effects of pH to the human periodontal ligament cells in vitro, especially on the cell morphology, attachment, activity, vitality and viability. Human periodontal ligament cells were cultured from extracted tooth for non-periodontal reason. Immediately after extraction, any soft tissue adhering to the cervical parts of the roots was carefully removed with a sterile curette. To produce different pH levels in the media, Eagle's MEM was adjusted from pH 6.6 to 8.2 in 0.2 intervals with 1 M NaOH and 1 N HCl. After cultivation, Then, Periodontal ligament cells were cultured at pH ranging from 6.6-8.2. attachment assay was done at 1, 2 day incubation and activity assay was done at 1, 2, 3 day incubation. The experiments were evaluated by scaning electron microscopic techniques (HITACHIX-650 Scaning Electron Microanalyzer, Tokyo, Japan), MTT assay, and the cultured periodontal ligament cells were fixed in neutral formalin for 24 hours and immunohistochemically processed by PCNA for proliferating ability. The surviving cells in the medium showed slightly increased volume and widening intercellular distances at low concentration of pH than control group (pH 7.4), and apparently shrinkage at high concentration of pH than control group (pH 7.4). The results of the statistical analysis from the experiment on attachment, vitality and viability were as follows. Attachment of periodontal ligament cells at 1st and 2nd day, similar attachment rate of low concentration pH compared with control value (pH 7.4). But above pH 8.0, attachment rate were statistically significant decrease from control value(P<0.05). Periodontal ligament cell's activities were maximum at pH 7.6 by MTT assay. Similar with control value at low concentration of pH. But, the activities were statistically significant decrease at high concentraration of pH(P<0.05). Cellular proliferating rate (PCNA index) were statistically significant decrease from control value at low and high concentration of pH(p<0.05). This results suggested that hjgh concentration pH, in other words, alkali pH was cytotoxic effects on human periodontal ligament cells in vitro.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.248-256
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• 2020

This study aimed to evaluate the effects of national dental screening for children in Korea in the aspects of prevention of dental caries, the number of treatments related to dental caries, and cost of dental care. The study used the national cohort data on children health screening provided by National Health Insurance Service, and analyzed 32,937 1st dental screening, 22,608 2nd dental screening, 13,708 3rd dental screening, and 241,043 cases from the dental care of 27,944 children born in year 2008 and 2009. The decayed-filled teeth index and decayed-filled person rate, calculated from the results of the 2nd and 3rd dental screening, decreased as the number of preceding dental screening increased. Glass ionomer and amalgam restoration, pulp treatment of primary teeth and extraction of primary canine and molar were shown to decrease as the number of examined dental screening increased, and the total cost of dental care covered by national health insurance also decreased as the number of dental screening increased. In conclusion, national dental screening for children is an efficient and economical oral health care method that prevents dental caries and lowers the possibility of dental caries related treatment, thereby reducing cost of dental care.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.158-163
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• 2016

Mushroom surveys and collections were conducted in the western and eastern forest areas in Cambodia, and then fungal biodiversity was analyzed by identifying mushrooms. One thousand and three hundreds eighty three specimens were identified by morphological and genetical characteristics, and were classified into 238 species, 160 genera, 52 families, 15 orders, and 3 phylums. The collected mushrooms were immersed in 70% ethyl alcohol for DNA extraction, and the rest of them were dried in the portable mushroom dryer for 12 hrs. Among these mushrooms, the genera Mycena (8.7%), Ganoderma (5.6%), Microporus (5.3%), Marasmius (4.2%), Marasmiellus (3.0%), Phellinus (2.5%), Trametes (2.5%), Hygrocybe (1.9%) and Pycnoporus (1.5%) were dominant. In the western Cambodia, 1,061 specimens were collected from Koh Kong forests, while 263 specimens were collected from the eastern Cambodia, Seima and Mondulkiri forests. Elevations of surveyed sites were ranged from 0 to 750 m above sea level. The number of species observed in the elevation of 251-500 m was the highest as compared to the other ranges of elevation. Daldinia concentrica, Microporus vernicipes, Microporus xanthopus, Pycnoporus coccineus, Stereum hirsutum, and Stereum ostrea were commonly distributed in all ranges of elevation, while the distribution of Ceratomyxa fruticulosa, Panus fulvus, Schizophyllum, Trametes versicolor, and Tyromyces chioneus were limited under 500 m. One hundred and forty one species including Amauroderma sp., Bjerkandera adusta, Trichaptum abietinum, and Tyromyces chioneus were collected only in Cardamom, while 20 species including Auricularia auricula-judae, Coriolopsis sanguinaria, Rigidoporus microporus, and Xylaria polymorpha were collected only in Seima. Ganoderma sp., Mycena sp., Marasmius sp., Microporus xanthopus, Phellinus sp., and Russula sp. were dominant species in both the western and eastern Cambodia. Species diversity indices in the eastern and western survey sites were 1.83 and 1.77, respectively, while evenness indices were 0.92 and 0.90. The species similarity index between two survey sites was 0.42.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.298-307
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• 2003

The purpose of this study was to investigate the distribution and differences of the cephalometric measurements between normal occlusion and the class III malocclusion. Kim's analysis was achieved and compared on both the 141 elementary school students with proper profile and normal occlusion and the class III malocclusion group at the age of 7 to 9, in Gwang-ju area and the results were as follows; 1. The ODI, APDI, IIA, UL showed statistically significant differences between normal occlusion and class III malocclusion(p<0.01). But, no significant difference existed in both CF and EI. 2. The mean value of ODI was 72.62, APDI 80.47 IIA 121.37 in normal occlusion. 3. The mean value of ODI was 64.45, APDI 87.31 IIA 129.89 in class III malocclusion. 4. ODI decreased as APDI increased, and the correlation coefficient was -0.576 in both normal occlusion and class III malocclusion. 5. The correlation coefficient related to EI was CF 0.777, LL -0.670, UL -0.588, IIA 0.485. It means that UL and LL were very sensitively reflected on EI.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.1
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• pp.23-40
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• 1999

The analysis of thiodiglycolic acid in urine has been used as an index of biological exposure to vinyl chloride. Unfortunately thiodiglycolic acid has a strong hydrophilic character, because it has two carboxylic groups, so that it can only be extracted with organic solvent with a great difficulty. Underivatized thiodiglycolic acid tends to tail because of non-specific interaction with the inert support. Therefore, esterification is the obvious first choice for derivatization of thiodiglycolic acid, particularly for gas chromatography. In this study, the focus of interest is to compare two method of esterifications (methylation and silylation). Methylation is to make the methyl ester of thiodiglycolic acid by reaction with diazomethane. Silylation is to make the trimethylsilyl ester of thiodiglycolic acid by reaction with N-trimethylsily-ldiethylamine. The results and conclusions are as the following: 1. The detection limit (sensitivity) of methylated thiodiglycolic acid was $5.00{\mu}g/m{\ell}$ and silylated thiodiglycolic acid was $3.07{\mu}g/m{\ell}$ by gas chromatography with flame ionization detector. 2. The optimal liquid-liquid extraction of thiodiglycolic acid was as following: To each of the tubes, $15m{\ell}$ of urine, concentrated sulfuric acid (pH 1 - 2) and 5 gsodium sulfate were added. The samples was extracted three times with $5m{\ell}$ ethylacetate each time. 3. The methylated thiodiglycolic acid was more stable than silylated thiodiglycolic acid in extractional solvent which contained humidity. 4. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.07324 in methylated thiodiglycolic acid with external standard calibration, and 0.07033 in methylated thiodiglycolic acid with internal standard calibration. 5. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.10914 in silylated thiodiglycolic acid with external standard calibration, and 0.13602 in silylated thiodiglycolic acid with internal standard calibration. From the above results, the analysis of methylated thiodiglycolic acid was more sensitive (limit of detection) than silylated thiodiglycolic acid by gas chromatography. However, the methylated thiodiglycolic acid was stable in the humidity and was separated sharply on chromatogram. Also, analysis of methylated thiodiglycolic acid was more precise (pooled coefficient of variation for 4 days) than silylated thiodiglycolic acid. In conclusion, it is established that the analysis of methylated thiodiglycolic acid is appropriate for biological monitoring of exposure to vinyl chloride.

• Journal of dental hygiene science
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• v.5 no.1
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• pp.13-17
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• 2005

This research was conducted in order to collect and arrange an oral health information needed the school oral hygiene as a part of a long term local community oral hygiene development to promote the oral health of the residents in Sung-Nam. After gathering the information of oral hygiene of 12-year old schoolchildren in Sung-Nam, these conclusions are reached: (1) The experience of dental caries in permanent teeth of 12-year old schoolchildren in Sung-Nam was revealed 74.7%, proportion of children with one or more caries in permanent teeth was 36.2%, and DMFT index was 2.75. (2) DT rate was 28.4% in total and regional difference has been revealed. In Sujung-Gu, DT rate was 36,8% and this was nearly as twice as 19.8% in Bundang-Gu. (3) For permanent teeth, fillings requirements for one surface were 26.6%, more that two surfaces were 13.3%. In addition, artificial crown treatment requirements were 1.8%, dental pulp treatment was 5.3%, and extraction requirement was 2.2%. In contrast, holders of pit and fissure sealant were only 27.1%. (4) In Sung-Nam, oral hygiene education campaign for 12-year old schoolchildren needs to be continued. Simultaneously, early stage examination and preventive approaches for decayed teeth such as pit and fissure sealant need to be considered for schoolchildren who have high tendency of dental caries and who are in areas which show high percentage of dental caries occurrence.

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.57-66
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• 1990

The author conducted a dental survey of college girl students and compared with that of college students 20 years and 10 years ago which based on the same criteria. The items of this survey included the prevalence of dental caries, DMFT and the kinds of restored materials. College girl students 2,294 were examined in May 1988, with the recommended criteria and method of W.H.O.. Among them, the data of 2,243 were analyzed and compared with the data of 1968 and 1978. The following results were obtained : 1. The average number of present teeth was $28.86{\pm}1.65$, which does not show much difference when compared to $29.00{\pm}1.94$ of 1968 and $28.97{\pm}1.64$ of 1978. 2. The prevalence of dental caries was 86.22%, which increased in comparison to 83.25% of 1968 and 84.92% of 1978. 3. DMF index was 19.98, which considerably increased in comparison to 14.56 of 1968 and 15.51 of 1978. 4. The number of DMFT was $5.75{\pm}5.04$ per student. Compared to $4.23{\pm}3.88$ of 1968 and $4.49{\pm}3.69$ of 1978, there is a considerable increase. I) The average number of decayed(D) teeth was $1.14{\pm}1.63$, which decreased from $1.16{\pm}1.57$ of 1968 and $2.09{\pm}2.16$ of 1978. II) The average number of missing(M) teeth was $0.23{\pm}0.73$, which also decreased from $0.69{\pm}1.11$ of 1968 and $0.32{\pm}0.79$ of 1978. III) The average number of filled(F) teeth was $4.39{\pm}4.91$, which increased from $2.38{\pm}3.33$ of 1968 and $2.09{\pm}3.17$ of 1978. 5. According to the analysis of filling material, filling baby including amalgam, gold inlay, resin, silicate cement and paladium inlay was 90.5%, which increased in comparison to 72.8% of 1968 and 83.6% of 1978. Among them, amalgam occupied 62.93%, which showed the most increase. On the other hand, crown and bridge was 6.5%, 3.0%, respectively, which showed continuous decrease from 12.1%, 15.1% of 1968 and 8.7%, 7.7% of 1978. Therefore, the prosthodontic treatment reduced due to the decrease of tooth extraction. In contrast, there is continuous increase of conservative treatment which maintaining natural tooth.