• Korean Journal of Soil Science and Fertilizer
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• v.51 no.1
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• pp.16-27
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• 2018

To predict the influence of volcano eruption on agriculture in South Korea we evaluated the dispersal ranges of the volcanic ashes toward the South Korea based on the possibilities of volcano eruption in Mt. Baekdu. The possibilities of volcano eruption in Mt. Baekdu have been still being intensified by the signals including magmatic unrest of the volcano and the frequency of volcanic earthquakes swarm, the horizontal displacement and vertical uplift around the Mt. Baekdu, the temperature rises of hot springs, high ratios of $N_2/O_2$ and $_3He/_4He$ in volcanic gases. The dispersal direction and ranges and the predicted amount of volcanic ash can be significantly influenced by Volcanic Explosivity Index (VEI) and the trend of seasonal wind. The prediction of volcanic ash dispersion by the model showed that the ash cloud extended to Ulleung Island and Japan within 9 hours and 24 hours by the northwestern monsoon wind in winter while the ash cloud extended to northern side by the south-east monsoon wind during June and September. However, the ash cloud may extent to Seoul and southwest coast within 9 hours and 15 hours by northern wind in winter, leading to severe ash deposits over the whole area of South Korea, although the thickness of the ash deposits generally decreases exponentially with increasing distance from a volcano. In case of VEI 7, the ash deposits of Daejeon and Gangneung are $1.31{\times}10^4g\;m^{-2}$ and $1.80{\times}10^5g\;m^{-2}$, respectively. In addition, ash particles may compact close together after they fall to the ground, resulting in increase of the bulk density that can alter the soil physical and chemical properties detrimental to agricultural practices and crop growth.

• Journal of Embryo Transfer
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• v.19 no.1
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• pp.43-51
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• 2004

The present study was conducted to investigate the effects of fusion and/or activation protocol on in vitro development of porcine somatic cell nuclear transfer (SCNT) embryos. Porcine fetal fibroblast cells were transferred into the perivitelline space of enucleated in vitro matured oocytes. Cell fusion and activation were induced simultaneous fusion/activation (SA) or delayed activation (DA) with or without cytochalasin B (CB) treatment with electic pulses in 0.28 M mannitol-based medium. The SCNT embryos were cultured in vitro for 7 days and stained with Hoechst 33342 to determine the number of nuclei. After 7 days culture, cleavage and blastocyst formation rates were 72.4% and 7.6% in SCNT and 76.3% and 20.4% in parthenotes. To examine the effect of electric field strengths on development of SCNT embryos, oocytes were fused two pulses of 110 V/mm, 130 V/mm or 150 V/mm for 30 sec post-injection. The fusion and cleavage rates in 130 V/mm group (70.2% and 72.6%) and 150 V/mm group (72.6% and 70.5%) were higher (P<0.05) than 110 V/mm group (47.1% and 48.6%), respectively. However, the rate of embryos developing to the blastocyst stage (8.1%, 9.7% and 10.7%) were not different among three groups. The cleavage rates and the blastcyst formation rates were not different among three treatment groups (SA group, 71.4% and 9.7%; SA+CB treatment group, 74.7% and 8.0%; DA+CB treatment group, 70.8% and 11.2%, respectively). And, no different in the number of cells in blastocysts was observed among the three groups (22.5$\pm$12.8, 23.3$\pm$11.2 and 21.6$\pm$10.4, respectively). These result suggest that two pulses of 130 V/mm or 150 V/mm for 30 sec with SA treatment or DA treatment are enough for fusion/activation of porcine somatic cell nuclear transfer (SCNT) embryos to develop to the blastocyst stage.

• Journal of Chest Surgery
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• v.38 no.3 s.248
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• pp.214-220
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• 2005

Extended transseptal approach can provide an excellent view of the mitral valve but the safety of this approach is controversial because this incision requires transaction of the sinus node artery, which in most cases and can result postoperative arrhythmia. The purpose of this study was to evaluate perioperative and longterm conduction disturbances and the cardiac rhythms of patients who underwent an extended transseptal approach for mitral valve surgery. Material and Method: Postoperative cardiac rhythms were analyzed in the 164 consecutive patients who received mitral valve replacements with a extended transseptal approach between March 1992 and July 2003. Result: Of the 84 patients in normal sinus rhythm, 34 ($39\%$) had developed transient junctional rhythm and atrial fibrillation after operation, lasting less than 72 hours in most of cases. No intractable arrhythmias occurred. Most of these arrhythmia were not detected at the time of discharge and only 8 patients ($9\%$) had atrial fibrillation at discharge. Postoperative PR intervals increased for 1 week, then decreased within 2 weeks postoperatively, and returned to normal range by 6 months postoperatively. During the postoperative period, 4 of the 78 patients with preoperative atrial fibrillation developed normal sinus thythm. Conclusion: The post-operative arrhythmias were temporary and showed no significant complications after extended transseptal approach for the mitral valve surgery.

• The Korean Journal of Mycology
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• v.14 no.2
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• pp.121-130
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• 1986

Factors affecting the productivity of cellulolytic enzymes and the mycelial growth of Ganoderma lucidum CAFM 9065 were examined in synthetic media. Among the carbon sources tested, Na-CMC was the best for the production of avicelase CMC ase, and cellobiose for ${\beta}-glucosidase$. Soluble starch and cellobiose were the best for the mycelial growth. The optimum concentration of Na-CMC for the production of the enzymes was 1.0 %, and mycelial growth increased remarkably with the higher concentration of Na-CMC. Glucose inhibited the production of the enzymes, but stimulated the mycelial growth. Among the nitrogen sources used, peptone was the most effective for the production of the enzymes, and the appropriate concentration of peptone was 0.2%. The mycelial growth was stimulated with the increase of the concentration of peptone up to 0.5%. The optimum concentration of $KH_2PO_4$ for the production of the enzymes and mycelial growth was 0.3 and 0.2%, respectively. The optimum concentration of $MgSO_4{\cdot}7H_2O$ for the production of the enzymes and mycelial growth was 0.02%. The production of the enzymes was facilitated by folic acid at a low concentration (0.03 mg/l), and mycelial growth by inositol. The optimum temperature for the production of the enzymes and mycelial growth was $30^{\circ}C$. The optimum pH for the production of avicelase and ${\beta}-glucosidase$ was 5.0 equally and CMCase 5.5. The activities of avicelase and CMCase were the highest at 8 and 10 days of culture, respectively and that of ${\beta}-glucosidase$ at 16 day culture. The growth of mycelium was the highest at 12 days of culture at pH 5.0.

• Tuberculosis and Respiratory Diseases
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• v.45 no.3
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• pp.529-535
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• 1998

Background: Interleukin-4 plays an important role in pathogenesis of asthma, especially in developing atopy by means of switching B lymphocytes to produce IgE. It has been shown that there is polymorphism in the Interleukin-4 promoter region, transversion of cytosine to thymine at-598 from translation initiation site of IL-4 gene. There has also been quite a few works to reveal the role of the polymorphism of IL-4 gene in patients with asthma. We performed this investigation to determine the role of the polymorphism in the severity of symptoms of patients with asthma. We also examined the frequency and the type of the polymorphism in asthmatics compared with non-asthmatics as well. Method: The subjects enrolled in this study were 49 asthmatics and 33 non-asthmatics. All the asthmatics were classified as mild and moderate to severe by the NHLBI/WHO Workshop. DNA from both asthmatics and non-asthmatics was extracted, then performed ARMS(Amplification Refractory Mutation System) as well as RFLP using BsmFl restriction enzyme in order to confirm the polymorphism of Il-4 gene. Results: There was no significant difference in the occurrence of polymorphism of the IL-4 promoter sequence between asthm and non-asthma groups(P=0.7). Among those with polymorphisms, the number of C/C type was slightly more than C/T type in both asthmatics and non-asthmatics, 26 vs 21 in asthmatics and 18 vs 15 in non-asthmatics, which was, however, insignificant statistically. No significant relationship between the severity of asthma and the polymorphism was found(P=0.7). Conclusion: There was no significant difference between the severity of asthma and the IL-4 promoter polymorphism(P=0.709). Interestingly, the frequency of the polymorphism in both asthmatics as well as non-asthmatics was found to be even higher than that occurred in Caucasians. However, no significant difference in the frequency of the polymorphism was found in both groups.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.147-153
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• 1982

Nitrate and nitrite, which readily produce N-nitrosamines by reaction with secondary amines, are widely distributed in natural products such as vegetables and cereals, and are also used as a color fixation in meat products or fish roes. This experiment was carried out to determine the contents of nitrate and nitrite in foods such as fermented sea foods and fresh vegetables purchased at markets in Korea. The contents of nitrate were $0.74\sim13.81\;ppm$ for fermented sea foods and $4.0\sim1,572.5\;ppm$for fresh vegetables. As for vegetables, the nitrate levels of edible herbs were relatively higher than those of greens, fruits and rootcrops. The nitrite contents in fermented demoisells(Chromis notatus), fermented shrimp, fermented small squid, fermented anchovy and salted Alaska pollack roe were very little, while those in fermented hairtail and fermented entrails were not detected. As for vegetables, nitrite levels found for cabbage and lettuce were relatively as high as 3.8 ppm and $2.5\sim2.9\;ppm$, respectively, but were not detected in Korean cabbage, green perilla leaf, pepper, garlic and burdock. Of vegetables, the nitrate values in the outer part of Korean cabbage, stems of water cress and leaves of green onion were higher than in the other parts. Little variety of the nitrate levels were found during 4 days storage. In the comparison of low temperature storage and room temperature storage, lettuce, pumpkin and spinach contained higher levels of nitrate at low temperature storage, while eggplant and green onion, at room temperature storage.

• Journal of Nutrition and Health
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• v.51 no.4
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• pp.330-339
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• 2018

Purpose: This study examined the dietary habits and nutritional status of young children in Korea. Methods: Data were collected from the 2013 ~ 2015 KNHNES (Korea National Health and Nutrition Examination Survey) by health behavior interviews and the 24-hour dietary recall method. This study included 1,214 (445 aged 1 ~ 2 years, 769 aged 3 ~ 5 years) young children aged 1 ~ 5 years. To analyze the dietary status of young children, the general characteristics of young children and their mothers, their dietary behaviors and health factors, and nutritional status and frequently consumed foods were analyzed. Results: The starting time of bovine milk and weaning were 14 ~ 15 months and 6.2 months, respectively. Eighty two percent of young children ate breakfast 5 ~ 7 times per week while only 2.3% of them skipped breakfast. The highest percentage (35.8%) of the frequency of eating-out was 5 ~ 6 times per week. The prevalence of asthma, atopy, and allergic rhinitis was significantly higher in young children 3 ~ 5 years old than in those 1 ~ 2 years old. The subjects with lower recommended energy intake were 44.1% and 57.4% of young children 1 ~ 2 years old and 3 ~ 5 years old, respectively. Most nutrients except calcium and potassium were taken enough. For the intakes of calcium and potassium, 51% and 64% of young children 1 ~ 2 years and 3 ~ 5 years old, respectively, were taking less than the recommended calcium intake, and 79.5% and 75.5% of young children 1 ~ 2 years and 3 ~ 5 years old, respectively, did not meet the recommended potassium intake. The frequently consumed foods of young children 1 ~ 2 years old were milk, white rice, apple, curd yogurt, and egg, and those of 3 ~ 5 years old children were milk, white rice, apple, egg, and mandarin. Conclusion: The results of this study can be used to provide basic data for the nutritional education of mothers and teachers and assist in the development of sustainable dietary programs for young children.

• 대한공업교육학회지
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• v.43 no.1
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• pp.1-19
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• 2018

As the BIM designing technology has been applied recently in the construction field, architectural design education in the field of work and university has been changing to 3D modeling. Nevertheless, architectural design & drafting education in the construction specialized vocational high school is not responding appropriately to change. Despite the fact that students need to have 3D modeling design ability, there is a very lack of 3D housing design instructional material that can satisfy the change. The purpose of this study is to develop BIM-based 3D modeling instruction material and apply to analyze effect on interest and task performance ability on Housing Design. The 3D modeling instruction material used in this study was developed through four stages of preparation, development, implementation and evaluation according to the PDIE model procedure. Also, the experimental design model for hypothesis testing was used nonequivalent control group pretest-posttest design. Based on the experimental design model, BIM-based 3D modeling instruction material was performed in the experimental group and 2D CAD-based standard instruction material was taught in the control group. Experimental treatment was conducted on the students of construction specialized vocatinonal high school, and applied to the subject of Professional Drafting in the 12 hours. Before and after the experimental treatment, the interest and task performance ability on Housing Design were tested. Based on the test results, we analyzed the effects of the 3D modeling instruction material through the independent samples t-test. The results of the study are as follows. First, BIM-based 3D modeling instruction material was developed of 'Housing Design & Drafting' unit on the subject of Professional Drafting in construction specialized vocational high school. Second, the application of 3D modeling instruction material has shown to be effective in improving students' interest. Third, the application of 3D modeling instruction material has shown to be effective in improving students' task performance ability on Housing Design.

• The Korean Journal of Nuclear Medicine
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• v.39 no.5
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• pp.278-283
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• 2005

Purpose: In prior study, we synthesized $^{99m}Tc$-galactosylated chitosan (GC) and performed in vivo biodistribution study, showed specific targeting to hepatocyte. The aim of this study is to evaluate the labeling efficiency and cytotoxicity of modified galactosylated chitosan compounds, galactosyl methylated chitosan (GMC) and HYNIC-galactosylated chitosan (GCH). Materials and Methods: GC, GMC and GCH were synthesized and radiolabeled with $^{99m}Tc$. Then, they were incubated for 6 hours at room temperature and human serum at $37^{\circ}C$. Labeling efficiencies were determined at 15, 30 m, 1, 2, 3 and 6 h after radiolabeling. To evaluate cytotoxicity, MTT assay was performed in HeLa and HepG2 cells. Results: In comparison with them of $^{99m}Tc$-GC labeling efficiencies of $^{99m}Tc$-GMC were significantly improved (100, 97 and 89%) in acetone and 96.3, 95.8 and 75.6% in saline at 15 m, 1 and 6 h, respectively). Moreover, $^{99m}Tc$-GCH showed more improved labeling efficiencies (>95% in acetone and human serum and >90% in saline at 6 h). In MTT assay, cytotoxicity was very low and not different from that of controls. Conclusion: These results represent that these compounds are radiochemically compatible radiopharmaceuticals, can be used in hepatocyte specific imaging study and in vivo gene or drug delivery monitoring.

• The Korean Journal of Petroleum Geology
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• v.11 no.1 s.12
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• pp.1-8
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• 2005

Seventeen exploratory wells have been drilled in the Block VI-1 of offshore Korea, which is located in the southern part or the Ulleung Basin. Gas show has been recognized from most of the wells, and gas and condensate have been accompanied in some wells. Commercial discovery of gas, accompanied by condensate, has been made from Gorae V well. The reservoir gases or the Dolgorae III, Gorae I, and Gorae V wells in the Ulleung Basin mainly consists of hydrocarbon gases (>93%). These gases are thermogenic wet gases which contain more than 96% of the methane and result from the cracking of petroleum or kerogen. Based on the chemistry and composition of the gases and stable isotope data, they seem to be generated from different source rocks. The condensates from the Gorae I and V wells are mostly generated from terrestrial organic matter. Lacustrine organic matter may not play an important role for the generation of these condensates. The condensates from the Gorae V wells consist predominantly of terrestrial organic matter but with minor subsidiary input from marine organic matter. The condensates from Gorse I and V wells may be generated from different source rocks. The thermal maturity level of the condensates from the Gorae V well ranges from early to middle oil generation zone and condensate from Gorae I reaches middle oil window. Correlation or the thermal maturation level of the condensates and organic matter in the sediments reveals that a depth of the generation of liquid hydrocarbons can be inferred to 3,000 m and 3,900 m for the Gorae V and I wells, respectively. Gorae V well, however, did not reach the target depth and the geochemical data of the Gorae I well were obscured due to the severe sediment caving in.