• Development and Reproduction
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• v.11 no.3
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• pp.167-177
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• 2007

In the present study, we isolated three human adult stem cells including adipose tissue-derived stem cells(HAD), umbilical cord-derived stem cells(HUC), and amnion-derived stem cells(HAM) and analysed their characteristics. And we examined whether HAD could be used as therapeutical cells for the heart diseases. Both HAM and HUC appeared very similar morphology but HAD was different. Doubling time of HUC was most fast, but total doubling numbers of HUC was same with HAM. Total doubling numbers of HAD was much more than others. Expression patterns of genes and proteins of three human adult stem cells were very similar. Also they were differentiated into adipocytes, osteocytes, and chondrocytes. In addition, they expressed many cardiomyocyte-related genes. But expression pattern of genes is a little different. When HAD were cultivated in the presence or absence of various combinations of BMP and FGF after 5-azacytidine expose for 24 h, expression of Cmlc-1, and ${\alpha}1c$ genes was significantly increased. However, expression of troponin T, troponin I and Kv4.3 genes was not changed. Based on these observations, it is suggested that HAD, HUC, and HAM might be used as potentially therapeutical cells for clinical application.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.74-80
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• 2012

Fish contain both the neurotoxin methyl mercury (MeHg) and nutrients important for brain development. The developing brain appears to be most sensitive to MeHg toxicity and mothers who consume fish during pregnancy expose their fetus prenatally. Although brain development is most dramatic during fetal life, it continues for years postnatally and additional exposure can occur when a mother breast feeds or the child consumes fish. This raises the possibility that MeHg might influence brain. We evaluated the relationship between fish consumption and mercury exposure levels in umbilical cord blood of the pregnant women of the city of Tongyeong city, Korea. A total of 159 pregnant women residing in the city of Tongyeong, Korea were recruited for the study between October 2010 and March 2011. Fish consumption was evaluated using food frequency questionnaires including detailed questions on fish consumption. We used ANOVA to estimated the particular relevance between the frequency of fish consumption and the umbilical cord blood mercury concentration, and other various factors. The average mean concentration of mercury levels in umbilical cord blood of pregnant women who participated in our study were $2.69{\pm}2.50ppb$, ranging from 0.01 to 14.80 ppb. The mean concentration of umbilical cord blood mercury exposure was lower than the level recommended by WHO (5.0 ppb), but the mercury exposure level exceeded the WHO recommended in 17 (10.7%) cases of umbilical cord blood. Mercury levels in cord blood of pregnant women were $2.04{\pm}2.00ppb$, ranging from 0 to 8.00 ppb in below 29 years old and $3.18{\pm}2.74ppb$, ranging from 0.01 to 14.80 ppb in more 30 years old. In this study, there was a significant difference for the frequency of eating fish between the groups (p < 0.01). The level of the groups that ate fish 3 to more times per week ($4.15{\pm}4.02ppb$) was significant higher as compared with the level of other groups that ate fish 1 to times per week ($2.63{\pm}2.22ppb$) and none per week ($1.06{\pm}1.44ppb$), respectively. We found that the mercury concentration of umbilical cord blood associate with fish consumption and this was statistically significant and this fact revels that fish consumption is positively related to mercury levels in the umbilical cord blood. We need systematic and periodic research on the general population to prevent mercury poisoning, which can be cause by low-level mercury exposure from dietary intake such as chronic fish consumption.

• Journal of Life Science
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• v.16 no.6
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• pp.1052-1059
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• 2006

The heat shock response is induced by environmental stress, pathophysiological state and non-stress conditions and wide spread from bacteria to human. Although translations of most proteins are stopped under a heat shock response, heat shock proteins (HSPs) are produced to protect cell from stress. When heat shock response is induced, conformation of HSF1 was changed from monomer to trimer and HSF1 specifically binds to DNA, which was called a heat shock element(HSE) within the promoter of the heat shock genes. Human HSF1(hHSFl) contains five cysteine(Cys) residues. A thiol group(R-SH) of Cys is a strong nucleophile, the most readily oxidized and nitrosylated in amino acid chain. This consideration suggests that Cys residues may regulate the change of conformation and the activity of hHSF1 through a redox-dependent thiol/disulfide exchange reaction. We want to construct role of five Cys residues of hHSF by redox reagents. According to two studies, Cys residues are related to trimer formation of hHSF1. In this study, we want to demonstrate the correlation between structural change and DNA-binding activity of HSF1 through forming disulfide bond and trimerization. In this results, we could deduce that DNA binding activity of DNA binding domain wasn't affected by redox for always expose outside to easily bind to DNA. DNA binding activity of wild-type HSF's DNA binding domain was affected by conformational change, as conformational structure change (trimerization) caused DNA binding domain.

• Journal of dental hygiene science
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• v.9 no.2
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• pp.225-230
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• 2009

This study executed questionnaire 388 high school boy students in Jeolla-bukdo Namwon from June 9, 2008 to 20th prepares basic data about boy student's oral health behavior, and examines closely the connection factor and plans oral health promotion. Questionnaire distributed getting classroom teacher's cooperation and reclaimed through classroom teacher after make questionnaire by students. The collected data executed Chi-square test and descriptive statistics using SPSS program and the result is as following. 1. Response that responded that students of 61.1% are 2 times in toothbrushing number of times on 1 day, and appeared by thing which 69.1% does toothbrushing most much after way in the morning, and cleans up and down by toothbrushing method was the most by 36.6%. A student of only 8.5% was using auxiliary oral hygiene devices. 2. The oral medical examination and treatment engine use experience rate was 93.6%, and students of 82.9% do treatment as reason by last oral medical examination and treatment use purpose and did coming to help. The 1 year within use experience rate was 47.7%, and students of 77.1% were satisfied for medical examination and treatment. 3. Toothbrushing frequency of smoked students appeared low compared to students woo do not smoke, and students, who do drinking, was expose toothbrushing number by 3 limes compared to students who do not. 4. The activity limitation experience rate by oral disease was 16.0%, and the year absence experience rate was 5.2%, and the studies achievement hindrance experience rate appeared by 13. 1%. As a result, is considered to strengthen on-time oral medical examination and oral health education, and need prevention and policy of early treatment putting first.

• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.452-459
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• 2006

Competition will usually develop between the opposing walls as the restorative resin shrinks during polymerization. Magnitude of this phenomenon may be depended upon cavity configuration and volume. The purpose of this sturdy was to evaluate the effect of cavity configuration and volume on microleakage of composite resin restoration that has margins on the enamel site only. The labial enamel of forty bovine teeth was ground using a model trimmer to expose a flat enamel surface. Four groups with cylindrical cavities were defined, according to volume and configuration factor(Depth x Diameter / C-factor) - Group I : 1.5 mm ${\times}$ 2.0 mm / 4.0, Group II : 1.5 mm ${\times}$ 6.0 mm / 2.0, Group III : 2.Omm ${\times}$ 1.72 mm / 5.62, Group IV : 2.0 mm ${\times}$ 5.23 mm / 2.54. After treating with fifth-generation one-bottle adhesive - BC Plus$^{TM}$ (Vericom, AnYang, Korea), cavities were bulk flted with microhybrid composite resin - Denfill$^{TM}$ (Vericom). Teeth were stored in distilled water for one day at room temperature and were finished and polished with Sof-Lex system. Specimens were thermocycled 500 times between 5$^{\circ}$C and 55$^{\circ}$C for 30 second at each temperature. Teeth were isolated with two layers of nail varnish except the restoration surface and 1 mm surrounding margins. Electrical conductivity (${\mu}$A) was recorded in distilled water by electrochemical method. Microleakage scores were compared and analyzed using two-way ANOVA at 95% level. The results were as follows: 1. Small cavity volume showed lower microleakage score than large one, however, there was no statistically significant difference. 2. There was no relationship between cavity configuration and microleakage. Factors of cavity configuration and volume did not affect on microleakage of resin restorations with enamel margins only.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.647-656
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• 1999

The purpose of this study was to investigate the shear bond strength and marginal microleakage of composite to enamel and dentin according to different treatment methods when the applied bonding agent was contaminated by artificial saliva. For the shear bond strength test, the buccal and occlusal surfaces of one hundred twenty molar teeth were ground to expose enamel(n=60) and dentin surfaces(n=60). The specimens were randomly assigned into control and 5 experimental groups with 10 samples in each group. In control group, a bonding system(Scotchbond$^{TM}$ Multi-Purpose plus) and a composite resin(Z-100$^{TM}$) was bonded on the specimens according to manufacture's directions. Experimental groups were subdivided into 5 groups. After polymerization of an adhesive, they were contaminated with at artificial saliva on enamel and dentin surfaces: Experimental group 1 ; artificial saliva was dried with compressed air. Experimental group 2 ; artificial saliva was rinsed with air-water spray and dried. Experimental group 3 ; artificial saliva was rinsed, dried and applied an adhesive. Experimental group 4 ; artificial saliva was rinsed, dried, and then etched using phosphoric acid followed by an adhesive. Experimental group 5, artificial saliva was rinsed, dried, and then etched with phosphoric acid followed by consecutive application of both a primer and an adhesive. Composite resin(Z-100$^{TM}$) was bonded on saliva-treated enamel and dentin surfaces. The shear bond strengths were measured by universal testing machine(AGS-1000 4D, Shimaduzu Co. Japan) with a crosshead speed of 5mm/minute under 50kg load cell. Failure modes of fracture sites were examined under stereomicroscope. The data were analyzed by one-way ANOVA and Tukey's test. For the marginal microleakage test, Class V cavities were prepared on the buccal surfaces of sixty molars. The specimens were divided into control and experimental groups. Cavities in experimental group were contaminated with artificial saliva and those surfaces in each experimental groups received the same treatments as for the shear test. Cavities were filled with Z-100. Specimens were immersed in 0.5% basic fuchsin dye for 24 hours and embedded in transparent acrylic resin and sectioned buccolingually with diamond wheel saw. Four sections were obtained from the one specimen. Marginal microleakages of enamel and dentin were scored under streomicroscope and averaged from four sections. The data were analyzed by Kruskal-Wallis test and Fisher's LSD. The results of this study were as follows. 1. The shear bond strength to enamel showed lower value in experimental group 1(13.20${\pm}$2.94MPa) and experimental group 2(13.20${\pm}$2.94MPa) than in control(20.03${\pm}$4.47MPa), experimental group 4(20.96${\pm}$4.25MPa) and experimental group 5(21.25${\pm}$4.48MPa) (p<0.05). 2. The shear bond strength to dentin showed lower value in experimental group 1(9.35${\pm}$4.11MPa) and experimental group 2(9.83${\pm}$4.11MPa) than in control group(17.86${\pm}$4.03MPa), experimental group 4(15.04${\pm}$3.22MPa) and experimental group 5(14.33${\pm}$3.00MPa) (p<0.05). 3. Both on enamel and dentin surfaces, experimental group 1 and 2 showed many adhesive failures, but control and experimental group 3, 4 and 5 showed mixed and cohesive failures. 4. Enamel marginal microleakage was the highest in experimental group 1 and there was a significant difference in comparison with other groups (p<0.05). 5. Dentin marginal microleakages of experimental group 1 and 2 were higher than those of other groups (p<0.05). This result suggests that treatment methods, re-etching with 35% phosphoric acid followed by re-application of adhesive or repeating all adhesive procedures, will produce good effect on both shear bond strength and microleakage of composite to enamel and dentin if the polymerized bonding agent was contaminated by saliva.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.123-136
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• 2014

Recently, online shopping has further developed as the use of the Internet and a variety of smart mobile devices becomes more prevalent. The increase in the scale of such shopping has led to the creation of many Internet shopping malls. Consequently, there is a tendency for increasingly fierce competition among online retailers, and as a result, many Internet shopping malls are making significant attempts to attract online users to their sites. One such attempt is keyword marketing, whereby a retail site pays a fee to expose its link to potential customers when they insert a specific keyword on an Internet portal site. The price related to each keyword is generally estimated by the keyword's frequency of appearance. However, it is widely accepted that the price of keywords cannot be based solely on their frequency because many keywords may appear frequently but have little relationship to shopping. This implies that it is unreasonable for an online shopping mall to spend a great deal on some keywords simply because people frequently use them. Therefore, from the perspective of shopping malls, a specialized process is required to extract meaningful keywords. Further, the demand for automating this extraction process is increasing because of the drive to improve online sales performance. In this study, we propose a methodology that can automatically extract only shopping-related keywords from the entire set of search keywords used on portal sites. We define a shopping-related keyword as a keyword that is used directly before shopping behaviors. In other words, only search keywords that direct the search results page to shopping-related pages are extracted from among the entire set of search keywords. A comparison is then made between the extracted keywords' rankings and the rankings of the entire set of search keywords. Two types of data are used in our study's experiment: web browsing history from July 1, 2012 to June 30, 2013, and site information. The experimental dataset was from a web site ranking site, and the biggest portal site in Korea. The original sample dataset contains 150 million transaction logs. First, portal sites are selected, and search keywords in those sites are extracted. Search keywords can be easily extracted by simple parsing. The extracted keywords are ranked according to their frequency. The experiment uses approximately 3.9 million search results from Korea's largest search portal site. As a result, a total of 344,822 search keywords were extracted. Next, by using web browsing history and site information, the shopping-related keywords were taken from the entire set of search keywords. As a result, we obtained 4,709 shopping-related keywords. For performance evaluation, we compared the hit ratios of all the search keywords with the shopping-related keywords. To achieve this, we extracted 80,298 search keywords from several Internet shopping malls and then chose the top 1,000 keywords as a set of true shopping keywords. We measured precision, recall, and F-scores of the entire amount of keywords and the shopping-related keywords. The F-Score was formulated by calculating the harmonic mean of precision and recall. The precision, recall, and F-score of shopping-related keywords derived by the proposed methodology were revealed to be higher than those of the entire number of keywords. This study proposes a scheme that is able to obtain shopping-related keywords in a relatively simple manner. We could easily extract shopping-related keywords simply by examining transactions whose next visit is a shopping mall. The resultant shopping-related keyword set is expected to be a useful asset for many shopping malls that participate in keyword marketing. Moreover, the proposed methodology can be easily applied to the construction of special area-related keywords as well as shopping-related ones.

• Sijohaknonchong
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• v.42
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• pp.151-185
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• 2015

The purpose of this study is to reveal the aspects of "Children" in Saseolsijo and its historical implication in Korean Classical Poetry. What was discussed can be summarized as follows: There are two types of children in Saseolsijo, one is silent, and the other is speaking. The silent child characteristics are such as being called and addressed by the poetic narrator, customary audience, passive attitude, etc. The speaking child characteristics are speaking subject, active attitude as sign of modernity. These phenomenon simply expose the differences of aesthetic order. The silent children is mainly to be utilized as a device to maximize the lyricism of the text as an ideologically product by the inner request of the poetic narrator and show identification discourse. The speaking child, gives the dynamics in text by heterogeneous discourse and informs aesthetic distance between "the reader and the text" as well and show distance discourse. These fragments from Saseolsijo's children are also found in previous genres. In the case of Hyangga, 'children' speak for solving others' desire but are targeted by poetic narrator as well. In the case of Goryosokyo, 'children' show activity and efforts to break forced silence by the poetic narrator through voluntary speaking. In Sijo's case, unlike other genres, some literary works show contents about disciplining children and the growth of children. However mostly targeted children by the poetic narrator are predominantly appeared from the discourse perspective. These aspects of children in previous genres including some of works in Saseolsijo are mainly associated with the appearance of medieval children. Unlike these, the new aspects of Saseolsijo's children show the cross-section of the signs of transition contemporary, from medieval to modern. Even if there are few literary works in these, speaking children with activity reveals novelty over medieval-imposed 'child-ness' by showing 'self', 'individual desire' strongly. This novelty is far from infants of the modern concept as naive and innocent children but these children are noted in that they show a part of modernity through various voices in the text, the comic(laughter), multiple point views, etc.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.4
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• pp.239-252
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• 2007

Objectives: In the present study, we examined the differentiation potential of human adipose-(HAD) and human umbilical cord-derived mesenchymal like stem cells (HUC) into cardiomyocytes. Methods: Cells were initially exposed to 5-azacytidine for 24h cells and then were cultivated in the presence or absence of activin A, TGF-$\beta$1, or Wnt inhibitor with various combinations of BMP and FGF. Assessment of cardiomyogenic differentiation was made upon the expression of cardiomyocyte-specific genes using RT-PCR. Results: HAD that cultivated in control medium for 4 weeks after 5-azacytidine expose showed new expression of TnT gene and increased expression of Cmlc1 and kv4.3 genes. However, HAD cultivated in the presence of combinations of BMP-4/FGF-4 (B4/F4) and BMP-4/FGF-8 (B4/F8) showed new expression of $\beta$-MHC gene and more increased expression of Cmlc1, TnT, TnI, Kv4.3 genes. Significantly enhanced expression of Cmlc1, TnT, and Kv4.3 genes were also observed compared to that cultivated in the control medium. Treatment of HUC with either 5-azacytidine or combinations of BMP and FGF did not affect the expression profile of these genes. However, when activin A or TGF-$\beta$1 was present in addition to the BMP-2/FGF-8 (B2/F8) after 5-azacytidine exposure, HUC exhibited new expression of $\beta$-MHC gene and increased expression of $\alpha$-CA, TnT and Kv4.3 genes. When Wnt inhibitor was present in addition to BMP and FGF, HUC showed new expression of Cmlc1 gene and increased expression of $\alpha$-CA, TnT, TnI and Kv4.3 genes. Conclusions: Based on these observations, it is suggested that HAD and HUC could differentiate into cardiomyocytes which might be used as therapeutic cells for the heart diseases.

• Korea journal of population studies
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• v.19 no.2
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• pp.175-205
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• 1996

The purpose of this study was to find the distribution of the variables on the quality of life and the determinants of the sexual attitude and behavior of the unmarried female workers. This study was surveyed to the 306 unmarried women who worked in the small and medium scale industries in Kyungin area and analyzed the respondent's knowledge of sex, sexual behavior, health behavior, health status, satisfaction of working condition and recognition of working environment. The result of this study could be summarized as follows: The respondent's age are mostly early of twenties and their education level are high school and more. They recognize that their health condition is not so good but they hardly try to improve health condition. They think that their working condition are mostly unsatisfied and they also believe that they expose themselves to the toxic working environment. Although their knowledge of sex are low they have few chances for the education of sex and family planning. Their attitude of premarital sex are conservertive but the rate of approval of living together before marriage are high and the rate of premarital sex is around 15 percent. The premarital sex behavior are positively related with family size, living condition, knowledge of sex and working period but the sex experiences are negatively related with working period and knowledge of sex. As a result we suggest that the sex education and consultative program are necessary for improving the quality of life of the unmarried working women in small and medium scale industries.