• Journal of dental hygiene science
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• v.14 no.3
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• pp.319-324
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• 2014

The aim of this study was to evaluate influences of titanium dioxide ($TiO_2$) concentrations and irradiation times on growth of Streptococcus mutans when irradiated by visible light (405 nm wavelength) and by ultraviolet light (254 nm wavelength). To find the optimal antibacterial concentration of $TiO_2$, 0.01, 0.1, 1.0, and 10.0 mg/ml $TiO_2$ suspension was prepared with sterilized distilled water. S. mutans cultured media was added to $TiO_2$ solution to set the final cell count to $10^4CFU/ml$. The photocatalytic reaction was induced by irradiating 254 nm and 405 nm lights for 10 minutes. To compare the bactericidal activities according to irradiation times, all photocatalytic reaction was carried out with 0.1 mg/ml $TiO_2$ for 0, 10, 20, 30, and 40 minutes with both lights. After the photocatalytic reaction, $100{\mu}m$ of the reaction mixture was immediately plated on brain heart infusion agar. These plates were placed at 5% $CO_2$, $37^{\circ}C$, for 24 hours and the bacterial colonies were counted. All experiments were performed in quintuplicate. One-way ANOVA was used to determine whether there were any significant differences between the $TiO_2$ concentrations or the irradiation times. The most effective concentration of $TiO_2$ for its photocatalytic bactericidal effect on S. mutans was 0.1 mg/ml when irradiated with 254 nm and 405 nm lights. The longer the irradiation time, the bigger the bactericidal effect for both wavelengths. Over 99% of bacteria in the inoculum were killed after irradiation with 254 nm for 20 minutes and with 405 nm for 40 minutes. In conclusion, a photocatalytic reaction of $TiO_2$ induced by visible light of 405 nm constitutes the bactericidal effect on S. mutans.

• Journal of Korean Academy of Dental Administration
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• v.5 no.1
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• pp.22-30
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• 2017

Objective: The purpose is to study the factors to impact on the satisfaction of field practice among dental hygiene students and to provide the basic data for the quality improvement of the field practices for dental hygiene students. Methods: A self-reported questionnaires were filled out by 108 dental hygiene students in C city. Questionnaires were composed with the general characteristics, satisfaction to major, and satisfaction to field clinical practice. The data was analyzed by chi-square statistics using SPSS 20.0 program. Results: The higher satisfaction to communication with professor or seniors in department was associated with the higher satisfaction to field clinical practice (p<0.05). The higher satisfaction to field clinical practice hours per week was associated with the higher satisfaction to field clinical practice (p<0.05). The higher interest to major subjects and the satisfaction to the laboratory environment were associated with the higher satisfaction to field clinical practice (p<0.05). Conclusions: The higher satisfaction to major was associated with the higher satisfaction to field clinical practice. Therefore, the systematic curriculum development is needed to improve the satisfaction with major and clinical practice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1018-1027
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• 2005

The purpose of this study was to investigate nutrients intake and health-related behaviors in elderly people residing in Gyeongsan-si, Gyeongbuk who have no problem in daily living. Information on general characteristics of the elderly, health-related behaviors and dietary habits were obtained by interview based on questionnare. Dietary nutrients intake data were obtained through the 24 recall method. The subject group of this study was composed of 113 males and 112 females, the average age being $73.1\pm6.06$ years old. In health related factors, $76.9\%$ of subjects exercised regularly. The rates of alcohol drinking and smoking showed to be $38.2\%\;and\;22.2\%$, respectively. There were many elderly with neuralgia, hypertension, and gastrointestinal disease, especially female were worse. Average heights of the subjects were lower than the standard established in the Korean Recommended Dietary Allowances, and average weights were similar to the standards. The mean BMI and WHR were 24.8 (male 23.7, female 25.7) and 0.92 (male 0.92, female 0.89), respectively. Most of the subjects had a regular meal pattern comsuming three meals a day, and many elderly, especially more than $79.5\%$ of female, prepared the meals for themselves. Mean daily energy intakes and RDA percentage of energy intakes of the male and female subjects were estimated as 1426.9kcal $(79.3\%)$ and 1381.3 kcal $(86.3\%)$, respectively. Mean daily intakes of nutrients were estimatied as 48.1g for protein, 411.3mg for calcium, 8.05mg for iron, 541.8 R.E. for vitamin A, 0.84mg for vitamin $B_1$, and 0.79mg for vitamin $B_2$. Most nutrients except protein, clacium, iron and vitamin $B_2$ were consumed over $75\%$ of the RDA. Female elderly showed significant lower intakes (p<0.05) for most of the nutrients except calcium, phosphorus and vitamin ethan the elderly male.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.137-144
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• 2002

To obtain the basic information about pedo-genetic properties and origin of the parent materials of "Yongil" series in Korea, this study was conducted. The soil characteristics such as chemical and sand particles of typifying pedon, and distributional patterns in the area were analysed. The typifying pedon of "Yongil" series was distributed on the top of rolling area in the eastern coastal area of Korea, Yonggan-ri, Heunghae-eup, Pohang-si, Gyongbuk province. The results are as follows; The "Yongil" series in Korea was distributed on the rolling hill under altituede of 50m, and was used for cultivated upland, and the total acreage about 376ha. The content of sand was more than 50%, however the clay content in the depth of 40~100cm of the soil profile rapidly increased. The medium sand (0.5~0.1mm in size) are dominant among sand fraction, but coarse one are rare. So the rate of medium to total sand was higher in IIB horizon as 0.62~0.76 than A and C horizons. The content of heavy minerals in medium sand was low as 1.0~6.6% and the ratio of quartz to feldspars was higher in Ap2 and B1 horizon as 1.7 than IIB horizon which had less than 1.39. The cumulative curves of sand particles in Yeongil series showed the well sorted and differ from residuum soils derived from sand stone, but similar to dune soils(Haeri series). So it could be deducted from this study that "Yeongil" series are aeolian deposits derived from aeolian materials and have bisequum profile; the upper part depth of 40cm was recent cover sand, the horizon of 40~100cm depth was developed in Pleistocene epoch from the same materials.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.296-305
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• 2006

The heterogeneity of crop transpiration is important to clearly understand the microclimate mechanisms and to efficiently handle the water resource in greenhouses. A computational fluid dynamic program (Fluent CFD version 6.2) was developed to study the internal climate and crop transpiration distributions of greenhouses. Additionally, the global solar radiation model and a crop heat exchange model were programmed together. Those models programmed using $C^{++}$ software were connected to the CFD main module using the user define function (UDF) technology. For the developed CFD validity, a field experiment was conducted at a $17{\times}6 m^2$ plastic-covered mechanically ventilated single-span greenhouse located at Pusan in Korea. The CFD internal distributions of air temperature, relative humidity, and air velocity at 1m height were validated against the experimental results. The CFD computed results were in close agreement with the measured distributions of the air temperature, relative humidity, and air velocity along the greenhouse. The averaged errors of their CFD computed results were 2.2%,2.1%, and 7.7%, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3075-3078
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• 2013

Background: KLK3 gene products, like human prostate-specific antigen (PSA), are important biomarkers in the clinical diagnosis of prostate cancer (PCa). G protein-coupled receptor RFX6, C2orf43 and FOXP4 signaling plays important roles in the development of PCa. However, associations of these genes with PCa in northern Chinese men remain to be detailed. This study aimed to investigate their impact on occurrence and level of malignancy. Methods: All subjects were from Beijing and Tianjin, including 266 cases with prostate cancer and 288 normal individuals as controls. We evaluated associations between clinical covariates (age at diagnosis, prostate specific antigen, Gleason score, tumor stage and aggressive) and 6 candidate PCa risk loci, genotyped by PCR- high resolution melting curve and sequencing methods. Results: Case-control analysis of allelic frequency of PCa associated with PCa showed that one of the 6 candidate risk loci, rs339331 in the RFX6 gene, was associated with reduced risk of prostate cancer (odds ratio (OR) = 0.73, 95% confidence interval (CI) =0.57-0.94, P = 0.013) in northern Chinese men. In addition, subjects with CX (CC+TC) genotypes had a decreased risk for prostrate cancer compared to those carrying the TT homozygote (OR =0.64, 95% CI = 0.45- 0.90, P = 0.008). The TT genotype of 13q22 (rs9600079, T) was associated with tumor stage (P=0.044, OR=2.34, 95% CI=0.94-5.87). Other SNPs were not significantly associated with clinical covariates in prostate cancer (P > 0.05). Conclusions. rs339331 in the RFX6 gene may be associated with prostate cancer as a susceptibility locus in northern Chinese men.

• Journal of Korean Society of Transportation
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• v.23 no.1
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• pp.93-102
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• 2005

An Origin-Destination (O/D) is considered as one of the important information in route choices and trip assignments. A household interview survey is deemed to be the traditional and the most widely used method in making sample O/D and its conversion to the total O/D. Some researchers have studied to estimate dynamic O/D from the relationship between link volumes and trip assignment model. Nowadays, owing to the recent rapid spread of cellular phones. Location information of the cellular phone through the Base Station(BS) is considered as an alternative to O/D estimation. In this study, the methodology of generating BS-based O/D and the methodology of converting this O/D into an administrative district-based O/D are proposed. The information of GPS positions and cellular BS positions have acquired by establishing GPS equipment and cellular phone on taxies in Cheongju. Three weeks data are collected and used in estimating O/D by matching them on a digital map. Scatter diagram and sample correlation coefficients are used to investigate the similarity of the GPS-based O/D pattern among weeks, among days, and among times in day. The results show that there are few significant differences among weeks. But there is a difference in O/C pattern between weekday and weekend. Furthermore, there is a difference between morning peak and afternoon peak. Two methodologies are proposed to convert BS-based O/D into an administrative district-based O/D. The first one is to use the distribution pattern of GPS coordinates, the other is to use the coverage area of the BSs. To validate such converted O/D, GPS O/D is used as a true value. The statical analyses through scatter diagram, MAE and RMSE shows that there is few significant defference of pattern between the estimated BS-based O/D and GPS O/D. In the case of using only cellular information, the methodology using coverage area of the BSs is recommended for estimating O/D.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.166-182
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• 2005

Background: Cyclin-dependent kinase (CDK) inhibitors are family of molecules that regulate the cell cycle. The CDKN2, a CDK4 inhibitor, also called p16, has been implicated in human tumorigenesis. The CDKN2 inhibits the cyclin/CDK complexes which regulate the transition from G1 to S phase of cell cycle. There is a previous report that homozygous deletion of CDKN2 region on chromosome 9p21 was detected frequently in astrocytoma, glioma and osteosarcoma, less frequently in lung cancer, leukemia and ovarian cancer, but not detected in colon cancer and neuroblastoma. However, little is known about the relationship between CDKN2 and laryngeal cancer. Therefore this study was initiated to investigate the role of CDKN2 in human laryngeal squamous cell carcinoma development.1) Materials and methods: We used 5 human laryngeal carcinoma cell lines whether they have deletions or losses of CDKN2 gene expression by DNA-PCR or RT-PCR, respectively. We examined 8 fresh frozen human laryngeal cancer tissues to detect the loss of heterozygosity (LOH) of CDKN2. PCR was performed by using microsatellite markers of short arm of human chromosome 9 (D9S126, D9S144, D9S156, D9S161, D9S162, D9S166, D9S171, D9S200 and D9SIFNA). For informative cases, allelic loss was scored if the signal of one allele was significantly decreased in tumor DNA when compared to the same allele in normal DNA. Results: The CDKN2 DNA deletion was observed in 3 cell lines. The CDKN2 mRNA expression was observed in only one cell line, which was very weak. LOH was detected in 7 cases (87.5%). Conclusion: These results suggest that CDKN2 plays a role in the carcinogenesis of human laryngeal squamous cell carcinoma.

• Journal of agricultural medicine and community health
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• v.27 no.1
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• pp.99-113
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• 2002

For this study a sample of 205 people, 66 males and 139 females, over 65 years of age, residing in C-gu of S-si and utilizing senior centers, were selected, The objective of the study was to provide basic data for health promotion program development provided by health centers. A questionnaire was used to collect date on general characteristics, health status, social health status and utilization rate for health services. The instruments used in this study were the Lawton scale, to measure daily routine function, the MMSE-K developed by Folstein and modified to fit the Korea situation, for mental health status, and the CES-Dtool developed by Radloff, for emotional health status. the SPSS Window program was used to calculate percentages. Tests of significance were done using t-test and ANOVA. Multiple regression analysis was used to identify variables influencing the use of health services. The results are as follows : Of those utilizing senior citizen centers, 40.9% of males and 17.3% of the female thought they were healthy. The average score for IADL was 7.4. The daily routine of female respondents consisted of buying household articles and drugs, and other IADLs such as riding the bus or subway alone. These resulted in a higher score compared to males. For emotional health, 7.6% of the males reported depression compared to 21.6% of the females. For mental health, 48.5% of the males and 28.8% of the females were found to be in the group suspicious for dementia. On social health, 57.6% of the males and 62.6% of the females reported no intimate human relations. Of those older people who had close human relations, 52.5% of the males indicated a friend as the closest person and 53.8% of the females, their children. On use of health services, there was a significantly higher need for mobile medical care services treatment for those with lower education levels and status of window/widower. There was a significantly higher need for health exmination services for those with lower levels of exercise, greater satisfaction with sleep, higher levels of oral health care, and higher social contacts. In conclusion, there is a need to provide varied programs for the promotion of health, along with parallel resolution of social, psychological and economic issues. It is recommended that health services for elderly people provided by the health centers be implemented with full recognition of these characteristics and differences.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.14-21
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• 2012

The object of the study, Yousang-Dae(流觴臺) and engraved Go broad text on the flat rock in Gangneung-si Yungok-myun Yoodung-ri Baemgol, reveals that the place was for appreciating arts like Yusang Goksu and Taoist hermit's games. three times of detail reconnaissance survey brought about the results as follows. There is a the text, Manwolsan(滿月山) Baegundongcheon(白雲洞天), engraved on the rock in Baegunsa(白雲寺) that had been built by Doun at the first year of King Hungang(in 875) of the United Shilla, became in ruins in the middle of Joseon, and then was rebuilt in 1954. The text is an invaluable evidence indicating that the tradition of Taoist hermit and Sunbee(classical scholars) culture has been generated in Baemgol Valley. According to the 2nd vol. of Donghoseungram(東湖勝覽), the chronicle of Gangneung published by Choi Baeksoon in 1934, there is a record saying that 'Baegunsa in Namjeonhyeon is the classroom where famous teachers like Yulgok Lee Yi or Seongje Choi Ok were teaching' that verifies the historic property of the place. In addition, the management of Nujeong(樓亭) and Dongcheon can be traced through Baegunjeong(白雲亭) constructed by Kim Yoonkyung(金潤卿) in Muo year, the 9th year of Cheoljong(1858) according to Donghoseungram and the completed version of Jeungboyimyoungji(增補臨瀛誌). Also, Baegundongdongcheon(白雲亭洞天), the text engraved on the standing stone across the stream from Yousang-Dae stone, was created 3 years after the Baegunjeong construction in the 12th year of Cheoljong(1861), which refers a symbolic sign closely related with Yousang-Dae. Based on this premise and circumstance, with careful studying the remains of 'Yusang-dae' Goksuro, we discovered that the Sebun-seok(細分石) controling the amount and the speed of moving water and the remains of furrows of Keumbae-soek(擒盃石) and Yubae-gong(留盃孔) containing water stream with cups through the mountain stream and rocks around Yusang-Dae. In addition, as 21 people's names engraved under the statement of 'Oh-Seong(午星)' were discovered on the bottom of the rock, this clearly confirms that the place was one of the main cultural footholds of tasting the arts which have characteristics of Yu-Sang-Gok-Su-Yeon(流觴曲水宴) until the middle of the 20th century. It implies that the arts tasting culture of Sunbees had been inherited centering on Yusang-dae in this particular place until the middle of the 20th century. It is necessary to be studied in depth because the place is a historic and unique cultural place where 'Confucianism, Buddhism, and Zen'were combined together. Based on the result of the study, the identification of 23 people as well as the writer of Yusang-Dae text should be carefully studied in depth in terms of the characteristics of the place through gathering data about appreciation of arts like Yusanggoksu. Likewise, we should make efforts to discover the chess board engraved on the rock described on the documents, thus we should consider to establish plans to recover the original shape of the place, for example, breaking the cement pavement of the road, additional excavation, changing the existing route, and so fourth.