• Tuberculosis and Respiratory Diseases
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• v.39 no.6
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• pp.511-516
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• 1992

Background: It is well known that cigarette smoking is the risk factor of lung cancer, chronic obstructive pulmonary disease and ischemic heart disease. But there are few reports about the immediate effect of cigarette smoking on the cardiopulmonary functions. The serum level of carbon monoxide increases during cigarette smoking. It is known that carbon monoxide increases respration rate, heart rate and cardiac output, with decrease in maximal oxygen consumption. So we have studied to determine the immediate effects of cigarette smoking on the cardiopulmonary function during exercise. Method: Thirteen healthy smoking male subjects were included in this study. Each subject was undertaken pulmonary function test and incremental exercise test on two separate days, one without smoking (control) and the other after smoking three cigarettes per hour for five hours. The order of the two tests was randomized. Results: 1) The mean age of the subjects was $25{\pm}4.9$ year-old and the mean smoking history was $6{\pm}5$ pack years. 2) The mean blood level of carbon monoxide on the smoking day was higher than that on the nonsmoking day ($5.97{\pm}1.34%$ vs. $1.45{\pm}0.83%$; p<0.01). 3) The mean maximal oxygen consumption on the smoking day was lower than that on the nonsmoking day ($2.09{\pm}0.32$ L/min vs. $2.39{\pm}0.32$ L/min; p<0.05). 4) The mean anaerobic threshold on the smoking day was lower than that on the nonsmoking day ($1.33{\pm}0.24$ L/min vs. $1.53{\pm}0.20$ L/min; p<0.05). 5) The mean heart rate at rest on the smoking day was higher than that on nonsmoking day ($84.38{\pm}11.06$ beats/min vs. $75.46{\pm}5.83$ beats/min; p<0.05). But the means of maximal heart rate on both days were not different. 6) The pulmonary function tests were similar on both days. Conclusion: There was no change in pulmonary function test, but the maximal oxygen consumption and anaerobic threshold were decreased on the smoking day. So it was concluded that cigarette smoking impaired the cardiovascular functions immediately during exercise.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.69-74
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• 2010

Purpose: The purpose of this study was to analyze the influence of palatal height on Korean vowels and speech intelligibility in Korean adults and to produce baseline data for future prosthodontic treatment. Material and methods: Forty one healthy Korean men and women who had no problem in pronunciation, hearing, and communication and had no history of airway disease participated in this study. Subjects were classified into H, M, and L groups after clinical determination of palatal height with study casts. Seven Korean vowels were used as sample vowels and subjects'clear speech sounds were recorded using Multispeech software program on computer. The F1 and the F2 of 3 groups were produced and they were compared. In addition, the vowel working spaces of 3 groups by /a/, /i/, and /u/ corner vowels were obtained and their areas were compared. Kruskal-Wallis test and Mann-Whiteny U test were used as statistical methods and P < .05 was considered statistically significant. Results: There were no significant differences in formant frequencies among 3 groups except for the F2 formant frequency between H and L group (P = .003). In the analysis of vowel working space areas of 3 groups, the vowel working spaces of 3 groups were similar in shape and no significant differences of their areas were found. Conclusion: The palatal height did not affect vowel frequencies in most of the vowels and speech intelligibility. The dynamics of tongue activity seems to compensate the morphological difference.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.346-353
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• 2011

Purpose: The peri-implant soft tissue is remodeled by the initial marginal bone resorption affecting the prognosis and esthetic result of treatment. Thus various designs on implant neck design are studied to preserve peri-implant bone. The purpose of this study is to review on the causes of initial marginal bone resorption, the configuration of peri-implant soft tissue, and the implant crestal module favorable in preserving peri-implant tissue. Materials and methods: The studies on the causes of initial marginal bone resorption and the implant crestal modules are researched and reviewed using Pubmed database. The implant crestal modules including one piece and two-piece implant, internal and external hex abutment, taper and butt joint connection, scalloped design abutment, and platform switching concept are reviewed. Results: A number of clinical and experimental studies preferred one piece implant to two-piece in preserving initial peri-implant tissue. For two piece implants, internal hex abutment and taper joint connection appear more favorable than external hex abutment and butt joint connection relatively. Controversial issues still exist on scalloped design requiring more studies on it. Although the rationale is not certain, the concept of platform switching seems favorable in preserving initial peri-implant tissue based on clinical and experimental studies. Conclusion: Each implant crestal module contains its own advantages and disadvantages with various controversial issues. In the aspect of preservation of initial peri-implant tissue, however, one-piece implant seems beneficial. In cases when two-piece implant is more appropriate due to prosthodontic concerns or any other problems, the application of platform switching concept, internal connection abutment, and taper joint connection may be favorable for the preservation of peri-implant tissues.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.576-583
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• 2005

Tooth formation is a complex developmental process that is mediated through a series of reciprocal epithelial-mesenchymal interactions. Several signal pathways and transcription factors have been implicated in regulating molar crown development, but relatively little is known about the regulation of root development. It was reported that NFI-C knockout mice showed abnormal root formation with normal crown. The aims of this study are to elucidate how the NFI-C regulate the determine of root shape and odontoblasts differentiation. We carried out immunohistochemistry using cytokeratin to investigate the role of Hertwig's epithelial root sheath and DSPP mRNA in-situ hybridization to conform the nature of root dentin during root development in NFI-C knockout mice. Cytokeratin reacted with all the HERS cells and the continuity of cytokeratin positive cells between the HERS cells and enamel epithelium was lost in the cervical region both wild and K/O types. After root dentin deposition cytokeratin positive-HERS cells showed irregularity and loss of polarity in the cervical region in K/O type. DSPP mRNA was strongly expressed in odontoblasts of crown and root dentin in wild type mice, whereas expression of DSPP mRNA was restricted in odontoblast of crown dentin in the K/O type. During root formation in NFI-C knockout mice, HERS normally grow out of the crown but fail to induce odontoblast differentiation in root portion. These results suggest that NFI-C may play important roles in odontoblast differentiation during root dentin formation.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.24-34
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• 2010

The aim of this study was to evaluate the effect of incorporated nano HA on the demineralization resistance and bonding strength of LC GIC in comparison with micro HA. Fuji II LC GIC was used as the control group and a base material for experimental groups. Two experimental groups were prepared. One was prepared by adding 15% micro HA to LC GIC by weight ratio (Exp. 1), and the other was prepared by adding 15% nano HA instead (Exp. 2). According to the results, the following conclusions could be obtained. 1. Observing under the CLSM, the control group showed thicker enamel demineralization layer than in the experimental groups, and the Exp. 2 group showed the thinnest demineralization layer. 2. In SEM analysis, there was greater enamel demineralization in the control group. The Exp. 2 group was more resistant to demineralization compared to the Exp. 1 group. 3. The bonding strength was found to be in the increasing order of control, Exp. 1, and Exp. 2 group (p < 0.05). 4. Observing the fractured surfaces under SEM after the bonding strength test was performed, there were bone-like apatite particles formed in HA-added experimental groups, and a greater number of bone-like apatite particles were formed in the Exp. 2 group compared to the Exp. 1 group.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.747-761
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• 2017

The purpose of this study is to analyze differences in the teaching practices of biology teachers according to their awareness of the importance of evolution. For this purpose, two teachers who experienced study of evolution and recognized its importance, along with two teachers with no experience in evolution education in the comparison group, were included in the sample. To observe teaching practices, two classes each on biological evolution and non-evolution were selected, recorded and transcribed. The content analyzed included the teachers' view on evolution education and teachers' evolution concepts reflected in teaching practice. As a result, the level of understanding of the teachers' evolution concept was unrelated to teachers' awareness of the importance of evolution. Instead, each teacher would not feel the need for religious beliefs or awareness of the importance of evolution to have a negative impact on the awareness of the importance of evolution. Inexperienced teachers tend to reject the retraining opportunities to recognize the importance of evolution. In addition, inexperienced teachers were only superficially aware of the evaluation and improvement of evolution presented in textbooks and curricula. In actual teaching practice analysis, inexperienced teachers' utilizing ratio of the evolution key concept was higher than that of experienced teachers. Only experienced teachers were aware of the misconceptions presented in their execution and described the causes that appear in these misconceptions. Teachers who recognized the importance of evolution were widely using the key concepts of evolution, as well as more practical in preventing the misconceptions related to evolution forms. It indicates that biology teachers who do not realize the importance of evolution in biology education need to experience explicit and practical education programs as well as instructional materials on evolution.

• Journal of Aquaculture
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• v.17 no.4
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• pp.275-281
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• 2004

The present study was conducted to evaluate dietary requirements for essential fatty acids (EFAs) such as linoleic acid (LA, l8:2n-6), -lenolenic acid (LNA, 18:3n-3), or docosahexaenoic acid (DHA, 22:6n-3), eicosapentaenoic acid (EPA, 20:5n-3) and arachidonic acid (ARA, 20:4n-6) in juvenile eel Anguilla japonica cultured in a recirculating system for 16 weeks. The experimental diets contained 50% crude protein, 10% crude lipid and 3800 kcal/kg energy.Brown fish meal and blood meal were used as the main protein sources, while coconut oil, com oil and linseed oil were used as the lipid source to yield target fatty acids ratios. At the end of the trial, the effects of essential fatty acids supplementation on weight gain (WG), specific growth rate (SGR), feeding efficiency (FE), proximate composition andwhole body fatty acids contents were examined. WG, SGR, and FEof eels fed diet D2, D3, was significantly higher (P<0.05) than those of fish fed the other diets. Whole body HUFA concentration of eels fed D 1 was significantly lower (P<0.05) than those fed the other diets. HUFA/SFA (saturated fatty acids) ratio of whole body in eels fed diets D2, D3 and D6 were significantly higher than that of eels fed diet D1 (P<0.05).DHA/EPA ratio of whole body in eels fed diet D7was significantly higher than those fed the other diets; and eels fed diet D5 showed the lowest DHA/EPA ratio among all the dietary treatments (P<0.05).Based on the experimental results, we concluded that LNA (n-3) and LA (n-6) were necessary for optimum growth of juvenile eel, and the dietary requirement of LNA and LA were 0.35∼0.5% and 0.5∼0.65%, respectively.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.196-205
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• 2013

This study showed the chemico-physical characteristics and sensory evaluation of beef loin and ribs with various kinds of cooking apparatus and methods like pan heating, boiling, grilling, steaming, cooking heating, charcoal heating and double layer pan heating. Double layer pan filled with Phase Change Materials(PCM) heating was also tested. Heating time of beef loin and ribs by oven heating was the longest as 55.5 and 25.7 min. Cooking loss of beef loin and ribs were 40.49%, 27.98% each and showed biggest in charcoal heating(p<0.05). In the chemical analysis, grilling resulted in the highest protein contents of 29.3% in the loin and double layer pan heating had 28.6% in the ribs. In the loin, 20.3% of crude fat was the highest in the double layer pan heating, and 21.9% of crude fat of ribs in the PCM heating(p<0.05). In the test of shearing forces, double layer pan heating had the lowest result of $9.14kg/cm^2$ in the loin and $7.03kg/cm^2$ in the ribs. In the 9 point-scale sensory evaluation, PCM treatment showed the best result of 7.67 in the juiciness of loin and single layer pan heating and grilling treatment had the highest score of 7.00 in the ribs. Loin in the PCM heating had 7.11 and ribs in the grilling had 7.13, showing the best in overall acceptability. With this experiments, we could find the chemico-physical and sensory characteristics of beef loin and ribs were affected by various cooking methods.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.217-229
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• 2010

Objective: Apoptosis plays an important role for the maintenance of the normal pregnancy. Expression of X-linked inhibitor of apoptosis (XIAP) is able to effectively prevent apoptosis and controls trophoblast cells death throughout placental development, but it is still unknown in the function of XIAP in trophoblast cells exposed to hypoxic condition, which is one of the factors causing preeclampsia. Therefore, we conducted to compare XIAP expression in normal and pre-eclamptic placenta tissues and analyzed the function of XIAP in HTR-8/SVneo trophoblast cell line exposed to hypoxic condition. Methods: The expression of XIAP was analyzed in placental tissues from the following groups of patients (none underwent labor): 1) term normal placenta (n=15); 2) term with pre-eclamptic placeneta (n=15); and 3) pre-term with pre-eclamptic placenta (n=11) using semi-quantitative RT-PCR, immunohistochemistry, and Western blot. In order to evaluate the function of XIAP in HTR-8/SVneo trophoblast cells under hypoxic condition, HIF-$1{\alpha}$ plasmids, and hypoxic condtion were transfected and treated into HTR-8/SVneo trophoblast cells for 24 hours, respectively. Results: We observed that XIAP are expressed in the syncytiotrophoblasts and syncytial knot of placental villi. The expression of XIAP was significantly decreased in preeclamptic placenta tissues than in normal placenta tissues without labor (p<0.05). Furthermore, we confirmed the XIAP expression in HTR-8/SVneo trophbolast cells exposed to hypoxia was translocated from cytoplasm into nucleus and decreased XIAP by hypoxic condition induced apoptosis in HTR-8/SVneo trophoblast cells through up-regulation of pro-apoptotic proteins. Conclusion: These results suggest that the expression of XIAP is involved in placental development as well as decreased expression of XIAP by hypoxia is associated with pre-eclampsia through inducing trophoblast cells apoptosis.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.439-458
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• 2013

Temporal and spatial variations of water quality were investigated in the Cheonsu Bay of Yellow Sea, Korea from 2010 to 2011. Water samples were collected at 16 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids (SS), chemical oxygen demand (COD), dissolved oxygen (DO), Chlorophyll a and nutrients. Spatial distribution patterns of all survey items were not clear among stations but the bimonthly variations were distinct except the bottom water of the suspended solids. The trend analysis by principal component analysis (PCA) during 2 years revealed the significant variations in water quality in the study area. Spatial water qualities were discriminated into 3 clusters by PCA; station cluster in the surface water 1, 2~11, and 12~16, the bottom water 1, 2~7, and 8~16. Annual bimonthly water qualities were clearly discriminated into 3 clusters by PCA. But tend of cluster in the surface and bottom water was difference, period most of the research was low in nutrient. Ecology-based water quality criteria was a good level of grade II. Bimonthly results are shown as III grade(normal) at June and August, II grade(good) at October and December and I grade for February and April. Water quality was showed by the input of fresh water same as those of Kyoungin coastal area, Asan coastal area, Gunsan coastal and Mokpo coastal area in the Cheonsu.