• Korean Journal of Microbiology
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• v.46 no.3
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• pp.240-247
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• 2010

Pseudomonas aeruginosa is a Gram (-) opportunistic human pathogen causing a wide variety of infections on lung, urinary tract, eyes, and burn wound sites and quorum sensing (QS), a cell density-sensing mechanism plays an essential role in Pseudomonas pathogenesis. In order to investigate the importance of QS in the Pseudomonas infections of Korean patients, we isolated 189 clinical strains of P. aeruginosa from the patients in Pusan Paik Hospital, Busan, South Korea. The QS signal production of these clinical isolates was measured by signal diffusion assay on solid media using reporter strains. While most clinical strains (79.4%) produced the QS signals as similar level as a wild type strain, PAO1 did, where LasR, the initial QS signal sensor-regulator was fully activated, a minority of them (4.2%) produced much less QS signals at the level to which LasR failed to respond. Similarly, while 72.5% of the clinical isolates produced QS signals enough to activate QscR, an another QS signal sensor-regulator, some few of them (9%) produced the QS signals at much lower level where QscR was not activated. For further analysis, we selected 74 clinical strains that were obtained from the patients under suspicion of Pseudomonas infection and investigated the total protease activity that is considered important for virulence. Interestingly, significant portion of them showed very low protease activity (44.6%) or no detectable protease activity (12.2%). When the biofilm-forming ability that is considered very important in chronic infection was examined, most isolates showed lower biofilm-forming activity than PAO1. Similarly, significant portion of clinical isolates showed reduced motility (reduced swarming activity in 51.4% and reduced twitching activity in 41.9%), or non-detectable motility (swarming-negative in 28.4% and twitching-negative in 28.4%). Our result showed that the clinical isolates that produced QS signals at the similar level to wild type could have significantly reduced activities in the protease production, biofilm formation, and motility, and some clinical isolates had unique patterns of motility, biofilm formation, and protease production that are not correlated to their QS activity.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.2
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• pp.360-377
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• 2016

Since after the 1986 economic reform policy(Doi Moi), the central highland in Vietnam has transformed into one of the largest coffee producing areas. The transformation had been supported by mass migration of ethnic Kinhs from the coastal lowland. It did not take long for the Kinh migrants to be the ethnic majority in the region. Meanwhile the growth of coffee industry entailed in socio-economic disparity, specially between Kinh migrants and native ethnic minorities. The disparity has becomed obvious not only between coffee farming Kinhs and non-coffee farming ethnic minorities but also between coffee farming Kinhs and ehtnic minorities. The previous literatures highlight the lack of human and social capital and the lagging modernization in ethnic minority societies. However, they fall short in showing the explicit processes why ethnic minority coffee farmers earn less than ethnic majority counterparts. With a case study of Dak Lak province, this research attempts to show the reason why there is income gap between Kinh and ethnic minority Ede coffee farmers by comparing their ways of producing coffee and selling their products. The results show that Ede's land productivity is significantly lower than Kinh's. It is because Ede farmers use less fertilizer due to the shortage of the capital. Also they often get into debt for coffee production and should pay it back right after the harvest. It deprives them of chance to raise earning by selling the coffee beans at a higher price.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1543-1550
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• 2009

The aim of this study was to examine and compare the eating habits, dietary intake patterns and nutrient intake status of children with and without atopic dermatitis by questionnaire during July, 2008. A total 388 subjects of 5th and 6th grade elementary school children (AG: atopic group, n=65, NG: non-atopic group, n=323) in Seoul and Ulsan areas participated in this study. The questionnaire included general characteristics, dietary habits, and atopy-related food frequency. One-day 24 hour recall was collected to estimate nutrient intakes of the subjects. The data were analyzed by Chi-square test for food frequency analysis and by t-test for nutrient intakes. Atopy-related foods included milk, buckwheat, beef, pork, chicken, crab, egg, mackerel, peach, and tomato. From the findings, AG had a more irregular eating habit than NG (p<0.05). In case of food frequency, AG tended to consume more atopy-related foods than NG (p>0.05). The nutrient intakes of AG were significantly lower than those of NG (p<0.05), but only intake of animal iron in AG was higher than NG (p<0.05). NG consumed more protein than AG (p<0.05). Although milk was a noted hypersensitive allergic food, frequency and the amount of milk intake were not significantly different between two groups. In conclusion, atopic children had eaten more atopy-related foods and less nutrient intakes. Therefore, it is necessary to educate on good nutrition and guide atopic children and their parents.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.887-897
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• 2000

Background : Since the exact pathogenesis of sepsis-induced ARDS has not been elucidated, the mechanisms of enhanced neutrophilic respiratory burst were probed in endotoxin primed neutrophils associated with the roles of phospholipase A2(PLA2), platelet activating factor(PAF) and apoptosis. Methods : In isolated fresh human neutrophils, effects of the inhibition of PLA2 and PAF on the apoptosis were examined by the method of Annexin-FITC/dual PIflow cytometry. The roles of PLA2 and PAF on the neutrophilic respiratory burst were also examined by measuring oxidant generation in cytochrome-c reduction assay. Activities of the PLA2 and lysoPAF acetyltransferase (lysoPAF AT) of the neutrophils were determined to understand the effect of endotoxin on these enzymatic activities which may be related to the neutrophilic respiratory burst and apoptosis. In addition, the role roles of PLA2 and PAF in neutrophilic adhesion to bovine endothelial cells were examined in vitro by neutrophil adhesion assay. To investigate the effect of oxidants on pulmonary surfactant, cytochemical ultrastructural microscopy was performed. To inhibit PLA2 and PAF, non-specific PLA2 inhibitor mepacrine (100 nM) and WEB 2086 (100 nM) or ketotifen fumarate (10 ${\mu}g$/ml) were used respectively in all in vitro experimental sets. WEB 2086 is PAF receptor antagonist, and ketotifen fumarate is a lyso PAF AT inhibitor. Results: The mapacrine treatment, provided and the endotoxin (ETX) treatment, resulted in increased apoptosis of neutrophils (p<0.001) while treatments of WEB 2086 and ketotifen did not. The inhibition of PLA2 and PAF decreased (p<0.001) production of oxidants from PMA-stimulated neutrophils. While endotoxin increased the PLA2 activity of neutrophils (p<0.01), mepacrine supressed (p<0.001) the activity, provided after treatment of ETX. The lyso PAF actyltransferase activity (lyso PAF AT) increased (p<0.01) after treatment of ETX. In contrast, mepacrine, WEB 2086 and ketotifen showed a tendency of decreasing the activity after treatment of ETX. The treatment of ETX incresed (p<0.001) neutrophil adhesion to endothelial cells, which was reversed by inhibition of PLA2 and PAF (p<0.01). The binding of oxidants to pu1monary surfactant was identified histologically. Conclusions : The enhanced neutrophilic respiratory burst by ETX plays a pivotal role in the pathogenesis of ARDS in terms of oxidayive oxidative stress. Increased production of oxidants from neutrophils is mediated by the activations of PLA2 and lyso PAF AT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1041-1051
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• 2005

In order to assure the safety of the seaweeds, we measured the contents of the trace metals in the seaweeds harvested from Korean coastal area. We collected 620 marine algal samples from fourteen areas, and then analyzed the trace metals such as Hg, Cd, Cr, Cu, Mn, Ni, Pb and Zn. The contents of Hg, Cd, Ni and Mn were higher in the seaweeds collected from Chungnam Taean area. The contents of Cr and Cu were higher in the seaweeds collected from Yeongdeok and Tongyeong area, respectively. And Pb and Zn were highly detected from the seaweeds of Ulsan area. The mean levels of trace metals were high in the order of Zn $(48.02\pm41.20{\mu}g/g)\;>\;Mn (34.63\pm38.95{\mu}g/g)\;>\;Cu(6.29\pm6.52{\mu}g/g)\;>\;Ni(2.17\pm4.00{\mu}g/g)\; >\;Cr(1.61\pm2.35{\mu}g/g)\;>\;Pb(1.28\pm2.37{\mu}g/g)\;>\; Cd(0.67\pm0.75{\mu}g/g)\;>\;Hg(0.02\pm0.02{\mu}g/g)$. Zn was consistently most abundant metal in all samples, followed by Mn and Cu, which are very important for human health. There were higher contents of Hg and Cd in brown algae, the contents of Cr, Cu, Mn, Ni and Pb in green algae, the content of Zn in red algae among them. Additionally, significant linear correlations were observed between a total 28 different pairs of metals, of them, the correlation factor between Cr and Ni showed the highest (r=0.374, p<0.001). The trace metal contents of seaweeds varied with habitats and kinds of samples, nevertheless they showed very safe level in edible seaweeds tested. Scytosiphon lomentaria, which has been known as a little use of food, have shown a clear selectivity for Cr and Pb. Among non-edible seaweeds, Sargassum thunbergii for both Cd and Mn, Lomentaria hakodatensis for Ni and Grateloupia prolongata for Zn have shown a clear selectivity, respectively. Therefore, these seaweeds could be useful as bioindicator for each trace metal pollution.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.661-674
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• 2005

The purpose of this study was to quantify and compare the level of MMP-2, MMP-8 in the healthy, inflammed gingival tissue and inflammed gingival tissue associated with type 2 DM. We investigate whether expression of MMP-2, MMP-8 is increased by chronic periodontitis associated with type 2 DM. Gingival tissue samples were obtained during periodontal surgery or tooth extraction. Based on patient's systemic condition & clinical criteria of gingiva, each gingival samples were divided into three groups. Group l(n=8) is clinically healthy gingiva without bleeding and no evidence of bone resorption or periodontal pockets, obtained from 8 systemically healthy patients. Group 2(n=8) is inflammed gingiva from patients with chronic periodontitis. Group 3(n=8) is inflammed gingiva from type 2 diabetic patients with chronic periodontitis. Tissue samples were prepared and analyzed by Western blotting. The quantification of MMP-2, MMP-8 was performed using a densitometer and statistically analyzed by ANOVA. MMP-2, MMP-8 was expressed in all samples including healthy gingiva and increased in group 3 compared to group 1 and 2, and showed that significant variation was observed between group 1 & 3 in MMP-8 results. In conclusion, this study demonstrated that human gingival tissue with chronic periodontitis associated to type 2 diabetes showed slightly elevated MMP-2, MMP-8 levels compared to healthy gingiva and non-diabetic inflamed gingiva.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.763-773
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• 2017

The purpose of this study is to investigate the impact of Argument-Based Inquiry (ABI) strategy on student's character competency. For this study, 51 grade 11 students (two classes) were selected to the role assignment (ABI-R group) and 46 students (two classes) were assigned to the non-role assignment group (ABI group). In the result, the role assignment group (ABI-R group) showed a statistically higher change in character competency than the group without role assignment (ABI group). Particularly, the ABI-R group has significantly higher grade than ABI group in empathy, responsibility, and respect among the sub-factors of character competency. However, in the case of the cooperation factor of character competency, the ABI group showed statistically significant higher grade than ABI-R group. The results of this study showed that Argument-Based Inquiry (ABI) as teaching and learning strategies in science can contribute to the enhancement of human character competency. In addition, we suggest that students should be actively involved in the class through role assignment, but it is necessary to present the class situation so that they can be actively engaged according to the problem situation rather than being fixed in a given role.

• Journal of Gastric Cancer
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• v.6 no.4
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• pp.214-220
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• 2006

Purpose: p53 is one of the most commonly mutated genes in human tumors. The aim of this study was to analyze p53 mutation in gastric cancer and its correlations with the clinicopathologic variables to clarify the usefulness of p53 mutation as a prognostic factor. Materials and Methods: Specimens from 331 patients with gastric cancer who underwent a gastrectomy between March 1999 and April 2001 at the Kyungpook National University Hospital were used. p53 gene mutations were assessed by using a polymerase chain-reaction single-strand conformation polymorphism (PCR-SSCP) analysis. The correlations between p53 gene mutation and clinocopathologic parameters were analyzed. Results: p53 mutations were found in 66 (19.9%) tumors. Among those 66 cases, mutations were seen in 23 tumors at axon 5, in 8 at exon 6, in 21 at exon 7, and in 17 at exon 8. Two mutations were shown in 3 tumors. Thiriy-six (23.1%) of 156 intestinal-type tumors and 19 (13.1%) of 145 diffuse-type tumors showed p53 gene mutation (P=0.007). The frequency of p53 gene mutation didn't show any significant differences according to age, sex, stage, location, or gross type. Exon 5 mutations showed more frequently in intestinal-type tumors than in diffuse-type tumors (9.7% vs. 2.8%, P=0.024), and p53 mutation were more frequent in lymph nodes metastasis group than lymph nodes non-metastasis group with statistical significance (25.0% vs 15.6%, P=0.034). The five-year survival rate showed no statistically significant difference with p53 mutation (P=0.704). Conclusion: p53 mutations assessed by PCR-SSCP had little value as a prognostic factor after gastrectomy in patients with gastric cancer.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.330-338
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• 2011

BACKGROUND: This study was conducted to investigate the agricultural product (Pulses, Lettuces, Pumpkins, Apples, Pears and Tangerines) in Korea, monitoring of cadmium (Cd) and lead (Pb) contaminations of agricultural products in cultivated areas and abandoned mine areas were investigated, and risk assessment was performed through dietary intake of agricultural products. METHODS AND RESULTS: The average contents of Cd and Pb ranged from 0.001 to 0.018 mg/kg and from 0.007 to 0.032 mg/kg respectively. The result was showed that contents of Cd and Pb did not exceed maximum residual levels established by CODEX except pumpkins and apples. The average daily intake were in the range of $1.06{\times}10^{-3}$ to $4.76{\times}10^{-2}{\mu}g/kg$ b.w./day at the mean and 95th percentile for Cd, $4.53{\times}10^{-3}$ to $8.35{\times}10^{-2}{\mu}g/kg$ b.w./day at the mean and 95th percentile for Pb for general population, based on the Korean public nutrition report 2008. The Hazard Index (HI) from the ratio analysis between daily exposure and safety level values was smaller than 1.0. CONCLUSION(s): This results demonstrated that human exposure to Cd and Pb through dietary intake of agricultural produces from abandoned mine areas might not cause adverse effect exceeding to those from non-contaminated areas.

• Journal of Intelligence and Information Systems
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• v.21 no.1
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• pp.161-177
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• 2015

With the rapid evolution of technology, the size, number, and the type of databases has increased concomitantly, so data mining approaches face many challenging applications from databases. One such application is discovery of fraud patterns from agricultural product wholesale transaction instances. The agricultural product wholesale market in Korea is huge, and vast numbers of transactions have been made every day. The demand for agricultural products continues to grow, and the use of electronic auction systems raises the efficiency of operations of wholesale market. Certainly, the number of unusual transactions is also assumed to be increased in proportion to the trading amount, where an unusual transaction is often the first sign of fraud. However, it is very difficult to identify and detect these transactions and the corresponding fraud occurred in agricultural product wholesale market because the types of fraud are more intelligent than ever before. The fraud can be detected by verifying the overall transaction records manually, but it requires significant amount of human resources, and ultimately is not a practical approach. Frauds also can be revealed by victim's report or complaint. But there are usually no victims in the agricultural product wholesale frauds because they are committed by collusion of an auction company and an intermediary wholesaler. Nevertheless, it is required to monitor transaction records continuously and to make an effort to prevent any fraud, because the fraud not only disturbs the fair trade order of the market but also reduces the credibility of the market rapidly. Applying data mining to such an environment is very useful since it can discover unknown fraud patterns or features from a large volume of transaction data properly. The objective of this research is to empirically investigate the factors necessary to detect fraud transactions in an agricultural product wholesale market by developing a data mining based fraud detection model. One of major frauds is the phantom transaction, which is a colluding transaction by the seller(auction company or forwarder) and buyer(intermediary wholesaler) to commit the fraud transaction. They pretend to fulfill the transaction by recording false data in the online transaction processing system without actually selling products, and the seller receives money from the buyer. This leads to the overstatement of sales performance and illegal money transfers, which reduces the credibility of market. This paper reviews the environment of wholesale market such as types of transactions, roles of participants of the market, and various types and characteristics of frauds, and introduces the whole process of developing the phantom transaction detection model. The process consists of the following 4 modules: (1) Data cleaning and standardization (2) Statistical data analysis such as distribution and correlation analysis, (3) Construction of classification model using decision-tree induction approach, (4) Verification of the model in terms of hit ratio. We collected real data from 6 associations of agricultural producers in metropolitan markets. Final model with a decision-tree induction approach revealed that monthly average trading price of item offered by forwarders is a key variable in detecting the phantom transaction. The verification procedure also confirmed the suitability of the results. However, even though the performance of the results of this research is satisfactory, sensitive issues are still remained for improving classification accuracy and conciseness of rules. One such issue is the robustness of data mining model. Data mining is very much data-oriented, so data mining models tend to be very sensitive to changes of data or situations. Thus, it is evident that this non-robustness of data mining model requires continuous remodeling as data or situation changes. We hope that this paper suggest valuable guideline to organizations and companies that consider introducing or constructing a fraud detection model in the future.