• Journal of Radiation Protection and Research
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• v.36 no.2
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• pp.93-98
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• 2011

We induced the activation of melanocytes in the epidermis of C57BL/6 mice by ultraviolet-B (UV-B) irradiation, and observed the effect of an herbal preparation (HemoHIM, HH) on the formation, and decrease of UV-B-induced epidermal melanocytes. C57BL/6 mice were irradiated by UV-B $80\;mJ{\cdot}cm^{-2}$ ($0.5\;mW{\cdot}sec^{-1}$) daily for 7 days, and HH was intraperitoneally, orally or topically applied pre- or post-irradiation. For the estimation of change of epidermal melanocytes, light microscopic observation with dihydroxyphenylalanine (DOPA) stain was performed. Split epidermal sheets prepared from the ear of untreated mice exhibited 13~15 melanocytes${\cdot}mm^{-2}$, and one week after UV irradiation, the applied areas showed an increased number of strongly DOPA-positive melanocytes with stout dendrites. But intraperitoneal, oral or topical treatment with HH before each irradiation interrupted UV-B-induced pigmentation and resulted in a marked reduction in the number of epidermal melanocytes as compared to the number found in UV-B-irradiated, untreated control skin. The number and size of DOPA-positive epidermal melanocytes were also significantly decreased in intraperitoneally injected or topically applicated group after irradiation with HH at 3rd and 6th weeks after irradiation. The present study suggests the HH as inhibitor of UV-B-induced pigmentation, and depigmenting agent.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.67-75
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• 2003

Purpose : Intravascular stent implantation for the treatment of postoperative branch pulmonary artery(PA) stenosis has been used successfully. However, the cross sectional area of contralateral branch PA does not regress in spite of the successful dilation of the stenotic branch PA after stent implantation. We analyzed the morphologic and hemodynamic factors on the size of branch PA after successful stent implantation. Methods : The subjects in our study were 23 children who had undergone stent implantaion from Jan. 1995 to Jul. 2002 in the Division of Yonsei Pediatric Cardiology. We evaluated the cross sectional area index(CSAI) of branch PA before and after stent implantation at follow-up catheterization. We also investigated factors such as residual pulmonary stenosis, pulmonary regurgitation(PR), systolic pressure of right ventricle, and lung perfusion scan. Results : The CSAI of the RPA without stenosis changed from mean $238{\pm}17mm^2/BSA$ to mean $249{\pm}20mm^2/BSA$(P=0.47), but didn't regress. The CSAI of the LPA with stenosis was increased effectively by stent implantation from the mean $102{\pm}12mm^2/BSA$ to mean $125{\pm}11mm^2/BSA$(P< 0.05). At follow up after stent implantation, the CSAI of PA is correlated with the residual PR fraction after stent implantation. Conclusion : In a group with increased residual PR, CSAI of RPA was found to be significantly increased between the pre- and post-stages of stent implantation. So, we suspect that the pulmonary regurgitation remaining after right ventricle outlet tract(RVOT) dilatation surgery is correlated with the increase in CSAI of RPA.

• Journal of the Korean Arthroscopy Society
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• v.13 no.1
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• pp.22-27
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• 2009

Purpose: To identify the damage of the articular cartilage and analyze the clinical results of the partial medial meniscectomy. Materials and Methods: From January 2001 to December 2004, forty-eight patients in the degenerative arthritis and medial meniscal tear of knee who undertook arthroscopic partial meniscectomy and were able to keep pace with the times follow-up for more than 3 years were enrolled in this study. Six cases were men and 42 were women, and the mean age was 55.7 years (40~78 years). The patients were classified into two groups according to the Outerbridge grade. Grade I and II were classified into group 1 and grade III and IV into group 2. Group 1 included 30 cases and group 2 included 18 cases. The result were analyzed according to the Tapper & Hoover classification and Lysholm knee scoring scale. And we measured the distance of medial joint space in standing anteroposterior (AP) view of both sides at the pre-operative and the last follow-up. Results: According to the Tapper & Hoover classification, 28 cases were excellent, 7 cases good, 8 cases fair, and 5 cases poor. Among group 1, 25 cases were excellent, 2 cases good, 2 cases fair, 1 case poor. However, among group 2, 3 cases were excellent, 5 cases good, 6 cases fair, 4 cases poor. Average Lysholm knee score was improved from 62.4 preoperatively to 94 postoperatively in group 1, and from 58 preoperatively to 77.9 postoperatively in group 2. The joint space narrowing showed no statistically significant difference in both knees standing AP view. Conclusion: The arthroscopic partial meniscectomy for a patient with the degenerative articular cartilage was an effective treatment. However, we could not satisfy the results, in cases of Outerbridge grade III and IV. In grade III and IV, the partial meniscectomy was not aggravated the cartilage damage.

• Membrane Journal
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• v.24 no.3
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• pp.213-222
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• 2014

In this study, 2-stage recirculation membrane process was developed for purification of high purity bio-methane for the vehicle fuel application. Pure gas permeation and mixture gas permeation test were done as a function of methane content and pressure in the feed using polysulfone membrane modules. 2-stage membrane plant was designed, constructed in a food waste treatment cite. Dehumidification, dry desulfurization, and desiloxane plants are installed for the removal of $H_2O$, $H_2S$ and siloxane in the biogas. Permeation test were done with the pre-treated methane mixture in terms of methane purity and recovery by adjusting the ratio of membrane area (1:1, 1:3, 2:2) in the first and second membrane modules in the plant. When membrane area of 2 stage increased to $3m^2$ from $1m^2$ at 1-stage membrane area of $1m^2$, the feed rate and $CH_4$ recovery at 95% methane purity were increased from 47.1% to 92.5% respectively. When the membrane area increased two-fold (1:1 to 2:2), $CH_4$ recovery increased from 47.1% to 88.3%. When the feed flow rate was increased, in 1:3 ratio, final purity of the methane is reduced, the methane recovery is increased. When operating pressure was increased, the feed rate was increased and recovery was slightly decreased. From this result, membrane area, feed pressure and feed rate could be the important factor to the performance of the membrane process.

• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.157-181
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• 2020

Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.2
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• pp.133-139
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• 2009

Purpose: In spite of many reports about Helicobacter pylori infection in children with functional gastrointestinal disorders, there are few reports about the influence of H. pylori infection to functional dyspepsia and gastric motility. Therefore, we studied the influence of H. pylori infection on gastric myoelectrical activity in children with functional dyspepsia. Methods: Between August 2006 and December 2008 upper gastrointestinal endoscopies with biopsies, the rapid urease test and/or $^{13}C$ urea breath test, and electrogastrography (EGG) were performed on 63 patients with histologic chronic gastritis; patients with chronic disorders were excluded. Comparisons about gastric myoelectrical activities were made between H. pylori-positive children (n=25) and H. pylorinegative children (n=38). Results: The percentage of pre- and post-prandial normogastria was relatively lower in H. pylori-positive children than H. pylori-negative children (80% vs. 65%, and 80% vs. 68%, respectively). Compared to H. pylori-negative children, H. pylori-positive children had lower postprandial predominant power (8.18${\pm}$22.36 dB and 32.20${\pm}$24.18 dB, respectively; p<0.01) and a lower power ratio (${\delta}P$; -1.28${\pm}$6.18 vs. +4.62${\pm}$5.93, respectively; p<0.01). Conclusion: It was suggested that the gastric myoelectrical activity in children with chronic gastritis can be influenced by H. pylori infection. Thus, this study indicates that H. pylori infection may be predictable in children with functional dyspepsia through analyzing the EGG parameters, and treatment may be considered in H. pylori-positive children with impaired gastric activity, especially in the lower prevalence area.

• Journal of Chest Surgery
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• v.33 no.9
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• pp.697-706
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• 2000

Background: Isolated lung perfusion(ILP) was developed as a new treatment approach to non-resectable primary or metastatic lung cancer, because of its ability to reduce systemic toxicity while delivering high-dose chemotherapeutic agents to the target organs. This research was planned to evaluate the direct toxic effect of high-dose cisplatin to the lung tissue during isolated lung perfusion. Material and Method: Fifteen mongrel dogs were divided in the perfusate for 40 minutes. The second group was composed of 5 mongrel dogs which underwent ILP with cisplatin 2.5 mg/Kg added to the perfusate for 30 minutes and 10 minutes with washing solution without cisplatin. The third group underwent the same procedure as the second group except cisplatin 5.0 mg/Kg in the perfusate. Activities of serum angiotensin converting enzyme(ACE), tumor necrosis factor-$\alpha$(TNF-$\alpha$), and concentration of serum lactate dehydrogenase(LDH) and blood urea nitrogen/creatinine (BUN/Cr) were analyzed in each groups at the time of pre-perfusion, 1 hour, 1 day, 1 week, and 2 weeks after ILP. Result: Serum ACE activities before and 1 hour, 1 day, 1 week, and 2 weeks after ILP in control group were 45.1$\pm$6.3, 44.6$\pm$9.3, 46.7$\pm$9.5, 50.8$\pm$9.1, 46.1$\pm$4.3 U/L. Those in cisplatin 2.5 and 5.0 mg/Kg groups were 49.4$\pm$12.6, 39.0$\pm$8.6, 42.3$\pm$15.9, 50.0$\pm$2.6, 53.8$\pm$8.3 and 55.5$\pm$12.3, 47.0$\pm$6.3, 45.1$\pm$6.9, 74.8$\pm$19.5, 60.2$\pm$12.0 U/L, respectively. Serum TNF-$\alpha$ activities in each group before and after ILP were 5.0$\pm$1.5 / 7.7$\pm$2.2 / 6.6$\pm$2.5 / 4.3$\pm$1.3 / 5.2$\pm$1.1(control), 8.7$\pm$1.6 / 9.9$\pm$2.2 / 7.9$\pm$1.5 / 6.3$\pm$2.2 / 7.4$\pm$2.4 (cisplatin 2.5 mg/Kg), and 6.9$\pm$0.7 / 8.9$\pm$3.4 / 7.9$\pm$4.0 / 3.3$\pm$0.9 / 5.8$\pm$1.3 pg/ml(cisplatin 5.0 mg/Kg). Mean LDH levels of each group were 225.7 / 271.3 / 328.9 / 350.8 / 255.7(control), 235.7 / 265.7 / 336.0 / 379.5 / 299.2 (cisplatin 2.5 mg/Kg), and 259.6 / 285.2 / 340.6 / 433.4 / 292.4 IU/L(cisplatin 5.0 mg/Kg). So there was no significant difference in serum ACE, TNF-$\alpha$, and LDH activity changes after ILP between the 3 groups. And, there was no significant changes in BUN/Cr in each groups, which was independent of ILP and perfused concentration of cisplatin. In addition, all dogs survived the ILP and there was no significant evidence of pulmonary vascular injury after 2 weeks of ILP with cisplatin. Conclusion: There was no harmful effect of cisplatin to the lund tissue of the mongrel dog up to 5.0 mg/Kg in perfusate. Therefore, it is perceived to be safe and effective to deliver high-dose cisplatin to the lung without pulmonary toxicity and renal damage with ILP.

• The Mathematical Education
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• v.30 no.1
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• pp.1-19
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• 1991

This study intends to provide some desirable suggestions for the development of application oriented mathematics curriculum. More specific objects of this study is: 1. To identify the meaning of application and modelling in mathematics curriculm. 2. To illuminate the historical background of and trends in application and modelling in the mathematics curricula. 3. To consider the reasons for including application and modelling in the mathematics curriculum. 4. To find out some implication for developing application oriented mathematics curriculum. The meaning of application and modelling is clarified as follows: If an arbitrary area of extra-mathematical reality is submitted to any kind of treatment which invovles mathematical concepts, methods, results, topics, we shall speak of the process of applying mathemtaics to that area. For the result of the process we shall use the term an application of mathematics. Certain objects, relations between them, and structures belonging to the area under consideration are selected and translated into mathemtaical objects, relation and structures, which are said to represent the original ones. Now, the concept of mathematical model is defined as the collection of mathematical objcets, . relations, structures, and so on, irrespective of what area is being represented by the model and how. And the full process of constructing a mathematical model of a given area is called as modelling, or model-building. During the last few decades an enormous extension of the use of mathemtaics in other disciplines has occurred. Nowadays the concept of a mathematical model is often used and interest has turned to the dynamic interaction between the real world and mathematics, to the process translating a real situation into a mathematical model and vice versa. The continued growing importance of mathematics in everyday practice has not been reflected to the same extent in the teaching and learning of mathematics in school. In particular the world-wide 'New Maths Movement' of the 19608 actually caused a reduction of the importance of application and modelling in mathematics teaching. Eventually, in the 1970s, there was a reaction to the excessive formallism of 'New Maths', and a return in many countries to the importance of application and connections to the reality in mathematics teaching. However, the main emphasis was put on mathematical models. Applicaton and modelling should be part of the mathematics curriculum in order to: 1. Convince students, who lacks visible relevance to their present and future lives, that mathematical activities are worthwhile, and motivate their studies. 2. Assist the acqusition and understanding of mathematical ideas, concepts, methods, theories and provide illustrations and interpretations of them. 3. Prepare students for being able to practice application and modelling as private individuals or as citizens, at present or in the future. 4. Foster in students the ability to utilise mathematics in complex situations. Of these four reasons the first is rather defensive, serving to protect or strengthen the position of mathematics, whereas the last three imply a positive interest in application and modelling for their own sake or for their capacity to improve mathematics teaching. Suggestions, recomendations and implications for developing application oriented mathematics curriculum were made as follows: 1. Many applications and modelling case studies suitable for various levels should be investigated and published for the teacher. 2. Mathematics education both for general and vocational students should encompass application and modelling activities, of a constructive as well as analytical and critical nature. 3. Application and modelling activities should. be introduced in mathematics curriculum through the interdisciplinary integrated approach. 4. What are the central ideas of, and what are less-important topics of application-oriented curriculum should be studied and selected. 5. For any mathematics teacher, application and modelling should form part of pre- and in-service education.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.429-435
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• 2009

Purpose: The purpose of this study was to assess the prognostic value of preoperative FDG-PET in colorectal cancer (CRC) patients with hepatic metastasis (HM). Materials and Methods: 24 CRC patients (M:F=14:10; age, $63{\pm}10$ yrs) with HM who had undergone preoperative FDG PET were included. Cure-intent surgery was performed in all the patients and HMs were controlled using resection (n=13), radio-frequency ablation (RFA) (n=7), and resection plus RFA (n=4). Potential prognostic markers tested were maxSUV of primary tumor, maxSUV of HM, maxSUV ratio of HM over primary tumor (M/P ratio), histologic grade, CEA level, venous/lymphatic/nerve invasion, T stage, N stage, no. of HM, no. of lymph node metastasis, and treatment modality of HM. Results: 14 CRC patients developed a recurrence with a median follow-up duration of 244 days, whereas 10 patients did not develop recurrence with a median follow-up duration of 504 days. M/P ratios but other potential prognostic markers were significantly higher in the recurrent patients ($0.72{\pm}0.14$) than recurrence-free patients ($0.54{\pm}0.23$) (p=0.038). M/P ratio only was found to predict recurrence by Cox multivariate analysis (hazard ratio 37.7, 95% confidence interval 2.01-706.1, p=0.016). The 11 patients with lower M/P ratio of <0.61 had significantly better disease-free survival rate than the 13 patients with higher M/P ratio (${\geq}0.61$) (p=0.026). Conclusion: maxSUV ratio of HM over primary tumor (M/P ratio) may be useful for prognosis prediction of CRC patients with HM. Higher FDG uptake of HM than that of primary tumor may indicate a more advanced status in stage IV CRC.

• Korean Journal of Microbiology
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• v.51 no.1
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• pp.7-13
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• 2015

Hydrotrope-combined copper (HCC) is a copper ($Cu^{2+}$)-based algicide, which is combined with a hydrotrope that keeps copper ion in solution to improve performance. This study assessed the growth inhibition effect of HCC against Microcystis aeruginosa which is one of the most common toxic cyanobacterium in eutrophic freshwater environment. Various HCC doses, ranging from 5.5 to $550{\mu}g/L$ as $Cu^{2+}$, were applied to either BG-11 or 1/4 diluted medium with low- or high-inoculum density of M. aeruginosa. Growth inhibition was monitored based on a decrease in chlorophyll-a content in culture medium during the incubation. Results showed that HCC significantly inhibited the growth of M. aeruginosa in a dose-dependent manner. In case of 1/4 diluted BG-11 medium, HCC dose as low as $5.5{\mu}g$ $Cu^{2+}/L$ completely inhibited the production of chlorophyll-a by M. aeruginosa. It was found that HCC did not induce any significant release of microcystin-LR from M. aeruginosa. Acute toxicity of HCC was tested using Daphnia magna, and the 24-h $EC_{50}$ value was 0.30 mg/L as $Cu^{2+}$ which was much higher than the actual inhibition dose. Ames test was performed using Salmonella enterica serovar Typhimurium TA100, and HCC showed no increase in the number of revertant colonies. The result suggested that HCC does not have any mutagenic potential in the aquatic environment. In addition, no genotoxic effect of HCC was also confirmed based on the SOS ChromoTest using Escherichia coli PQ37. Therefore, HCC could be used as a relatively safe and effective pre- and post-treatment agent to control hazardous algal blooming in aquatic environments.