• The Plant Pathology Journal
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• v.26 no.4
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• pp.313-320
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• 2010

Genetic instability of the rice blast fungus Magnaporthe oryzae has been suggested as a major factor underlying the rapid breakdown of host resistance in the field. However, little information is available on the mechanism of genetic instability. In this study, we assessed the stability of repetitive DNA elements and several key phenotypic traits important for pathogenesis after serially transferring two isolates though rice plants and an artificial medium. Using isolate 70-15, we obtained a total of 176 single-spore isolates from 10 successive rounds of culturing on artificial medium. Another 20 isolates were obtained from germ tubes formed at the basal and apical cells of 10 three-celled conidia. Additionally, 60 isolates were obtained from isolate KJ201 after serial transfers through rice plants and an artificial medium. No apparent differences in phenotypes, including mycelial growth, conidial morphologies, conidiation, conidial germination, appressorium formation, and virulence, or in DNA fingerprints using MGR586, MAGGY, Pot2, LINE, MG-SINE and PWL2 as probes were observed among isolates from the same parent isolate. Southern hybridization and sequence analysis of two avirulence genes, AVR-Pita1 and AVR-Pikm, showed that both genes were also maintained stably during 10 successive generations on medium and plants. However, one reversible loss of restriction fragments was found in the telomere-linked helicase gene (TLH1) family, suggesting some telomere regions may be more unstable than the rest of the genome. Taken together, our results suggest that phenotype and genotype of M. oryzae isolates do not noticeably change, at least up to 10 successive generations on a cultural medium and in host plants.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.3
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• pp.139-153
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• 2012

Objectives : NK cells are spontaneously cytotoxic lymphocytes. These are not only important parts in the first line of defence against bacterial and viral infections of outside, but they may also play a critical role in chronic viral diseases. NK cells kill their targets spontaneously, without the need for prior sensitization and class I MHC restriction by the regulation of cytolytic functions and secretion of a variety of cytokines, such as interleukin-12(IL-12), MCP-1, IL-6, TNF-${\alpha}$, IFN-${\gamma}$. In addition, macrophage and NK cells cooperate through the production of cell mediates. These cooperation and modulation are one of major factors to prevent for evading immune surveillance of cancer. Hence, it could be assumed that if any candidate to enhance activities of macrophage and NK cell, it is considered as a potentially useful agents against cancer. Methods : In our study, to investigate effect of fermented soybean extracts by Lactic acid bacteria (SFE, soybean fermented extracts) work on intestinal immune cell to maintain general immune modulating and anti-cancer activity. We analyzed NK cytotoxicity assay and gene expressions of cytokine related with macrophage and NK cell activity. Results : In vitro experiment, SFE was verified as safety material for cell toxicicty to tumor cell strain without any toxicity of tumor growth inhibition and various cell strain. Effects of macrophage activity stimulating directly by SFE measured induced cytokine. The studies showed that IL-12 production by stimulation of SFE depended on concentration from 0.16mg/mL to 0.63mg/mL with non toxicity to cell, and it was the best activity at 0.63mg/mL. Besides, the effective concentration of SFE producing TNF-${\alpha}$ is similar to IL-12, but it was the best activity at 1.25mg/mL. The level of MCP-1, IL-6 and IFN-${\gamma}$ depended on concentration from 0.16mg/mL to 10mg/mL, IFN-${\gamma}$ showed the best activity at the effective concentration of 0.63mg/mL. With the result of NK cell activity measurement, the spleen cell of mouse injected SFE had 1.5 times higher killing effect than non injected cell. Conclusions : The result of this studies is that Soybean fermetated extracts(SFE) has possibility to immune aided material for the function not only inhibition of microbial infection to macrophage but also activity of adaption immune and cellular immune system.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.722-729
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• 2015

Powdery mildew (PM) caused by Podosphaera aphanis is a major disease that can result in significant yield losses in strawberry (Fragaria ${\times}$ ananassa Duchesne). For preventing PM, pesticides are usually applied in strawberry. In this study, molecular markers were developed to increase breeding efficiency of PM-resistance cultivars by marker-assisted selection (MAS). An $F_2$ population derived from a cross between PM-resistance 'Seolhyang' and PM-susceptibility 'Akihime' was evaluated for disease resistance to PM and RAPD (random amplification of polymorphic DNA)-BSA (bulked segregant analysis). Among 200 RAPD primers tested, OPE10 primer amplified a 311bp-band present in with 331bp. Sequence alignment performed for searching polymorphisms and six single nucleotide polymorphism (SNP) were found in amplified regions. To develop polymorphic marker for distinguishing between resistant and susceptible, RAPD was converted to cleaved amplified polymorphic sequence (CAPS) marker. Among restriction enzymes associated with six SNPs, Eae I (Y/GGCCR) was successfully digested to 231bp in susceptible. The results suggest that the selected CAPS marker could be used for increasing efficiency of selecting powdery mildew resistant strawberry in breeding system.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.1
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• pp.115-119
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• 2010

As the subjects of education has been changed from the instructors to learners, a web-based self-directed learning which can accelerate the initiative of learners and can be free from the restriction of time and space has been received attention. In this paper, the web-based self-directed learning system was designed. For the design, to make the learners build their own lecture plan, the service was designed to provide three kinds of lectures of video clip, slide lecture, and e-text lecture that were focused on various lecture contents. In addition, a learner and an assistant was man to man matched to enable the on-line mentoring for mutual communication between learners and assistants. Implementation was carried out by three sets of module - Manager, Learner and Assistant - that were applied to the real educational activities. The survey on satisfaction for the education, efficiency of ability improvement, and educational intelligibility for the attendants on the education showed more than 67.2% of satisfaction in satisfaction for the education. Furthermore, more than 86.9% of attendants replied that their ability were improved after the education of this system. The educational system realized in this paper shows effectiveness for the self-directed learning.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.319-328
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• 2022

The purpose of this study was to investigate the relationship between depression due to the COVID-19 pandemic and park use behaviors using on line posts. During the period of the pandemic prevention activities, text data containing both 'park' and 'depression' were collected from blogs and cafes in the search engine of Naver and Daum, then analyzed using Text Mining and Social Network techniques. As a result, the main usage behaviors of park users who mentioned depression were 'look', 'stroll(walk)' and 'eat'. Other types of behaviors were connected centering around 'look', one of the communication behaviors. Also, from CONCOR analysis, as the cluster referred from communication behavior and dynamic behavior was formed as a single behavior type, it was considered park users with depression perceived the park as the space for communication and physical activities. As the spread of COVID-19 caused the restriction of communication activities, the users might consider parks as one of the solutions. In addition, it was considered that passive usage behaviors have prevailed rather than active ones due to the depression. Resulting outcomes would be useful to plan helpful urban park for citizens. It is necessary to further analyze the park use behavior of users in relation to the period of before/after the COVID-19 pandemic and the existence/nonexistence of depression.

• The Journal of Korean-Japanese National Studies
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• no.34
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• pp.77-123
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• 2018

The liberated korea has the estimated population 16 million in 1945, and added 2.5 million just after an year. The korean repatriates returned by way of 2 main routes. The returnees, Wol-Nam-Min(former residents in north korea), and repatriates from Manchuria came into south korea over the 38th division line. The other repatriates from japanese islands and pacific areas came into Busan port and the vicinity. The repatriates who returned from the China and the Japanese islands made up about 80% of the total added population. However, the influx of overseas repatriates who explosively increased between 1945 and 1946, declined abruptly in April of 1946, and at last illegal re-emigration group to Manchuria and Japan Appeared, who had repatriated from those areas. This study deals with the "re-migration phenomenon of 1946" in korea, mainly focuses on 1) the motivation for those who decided to remigrate, their prospects of resettlement in Manchuria and post war japan after re-migration, 2) the structural problems of the Korean society in 1946-1947, and 3) the social recognition for the people who letf for Manchuria and Japan. This study proved the cause and background of re-migration phenomenon. The Manchuria case, the local authorities wanted farmers and peasants who could cultivate the abandoned land which had been originally pioneered and reclaimed by korean poor peasants, who repatriated to korean peninsula. On the other hand, the korean repatriates had a hard time in tenanting farmland, and so much difficulty in getting farming tools including fertilizer. That's why they left korea for Manchuria again. The Japanese case, the korean repatriates had a tough life owing to the restriction of properties left in japan, while the inflation and food shortage in korea got worse and worst. Accordingly, many koreans tried illegal entrance into post war japan. This study is a part of clarifying the universality and specificity of post war repatriation and migration issues developed in the south Korea. Through this study, we can find how difficult it is for newly liberated areas to accommodate repatriates and make them ordinary nationals in harmonic way with successful social integration. and we can observe the social aspect and administrative ability of newly liberated south korea in detail, Because the present korea has faced with so many problems connected with immigration workers and re-setting with korean communities abroad, we should introspect these historical experience of our own.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.469-476
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• 2008

Recently, TOD gains popularity as a traffic solution measure of high density urban regeneration projects. The purpose of this study is to investigate traffic impacts of high density TOD projects, and to identify the issues to be resolved. For a case study, it chooses Gangnamgucheong station in Gangnam area served by two subway lines, and designates 400m radius from the station as a site for high-density development. The MOEs chosen for this study is traffic volume, time, distance, speed, and mode share. The SECOM model is adopted for traffic simulation. The analysis results show that high-density TOD is an effective tool for traffic improvement even with only one station area being implemented. It is found that the traffic volume increases near the station in nature where high-density development occurs, but it declines overall in the rest of Gangam area. The total travel time and distance of passenger vehicles decline, meaning that the traffic condition becomes better than before. With regulation on parking supply, the improvement becomes more vivid. In terms of the changes of traffic speed, both alternatives show 4.1% increase in speed, but the difference between alternatives is not quite noticeable because of the induced vehicle demand driven to the streets with improved traffic condition. The mode share changes occur for the benefit of subway ridership, because the study station is equipped with two subway line services. When mixed with parking supply restriction, the impact becomes clearer.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.25-25
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• 2022

Drought becomes frequent and severe because of continuous global warming, leading to a significant loss of crop yield. In soybean (Glycine max [L.]), most of quantitative trait loci (QTLs) analyses for drought tolerance have conducted by investigating yield changes under water-restricted conditions at the reproductive stages. More recently, the necessity of QTL studies to use physiological indices responding to drought at the early growth stages besides the reproductive ones has arisen due to the unpredictable and prevalent occurrence of drought throughout the soybean growing season. In this study, we thus identified QTLs conferring wilting scores and moisture contents of soybean subjected to drought stress in the early vegetative stage using an recombinant inbred line (RIL) population derived from a cross between Taekwang (drought-sensitive) and SS2-2 (drought-tolerant). For the two traits, the same major QTL was located on chromosome 10, accounting for up to 11.5% of phenotypic variance explained with LOD score of 12.5. This QTL overlaps with a reported QTL for the limited transpiration trait in soybean and harbors an ortholog of the Arabidopsis ABA and drought-induced RING-D UF1117 gene. Meanwhile, one of important features of plant drought tolerance is their ability to limit transpiration rates under high vapor pressure deficiency in response to mitigate water loss. However, monitoring their transpiration rates is time-consuming and laborious. Therefore, only a few population-level studies regarding transpiration rates under the drought condition have been reported so far. Via employing an Arduino-based platform, for the reasons addressed, we are measuring and recording total pot weights of soybean plants every hour from the 1^st day after water restriction to the days when the half of the RILs exhibited permanent tissue damage in at least one trifoliate. Gradual decrease in moisture of soil in pots as time passes refers increase in the severity of drought stress. By tracking changes in the total pot weights of soybean plants, we will infer transpiration rates of the mapping parents and their RILs according to different levels of VPD and drought stress. The profile of transpiration rates from different levels of severity in the stresses facilitates a better understanding of relationship between transpiration-related features, such as limited maximum transpiration rates, to water saving performances, as well as those to other drought-responsive phenotypes. Our findings will provide primary insights on drought tolerance mechanisms in soybean and useful resources for improvement of soybean varieties tolerant to drought stress.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.906-912
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• 2004

Helicobacter pylori infection is highly prevalent, as high as 2/3 of whole population infected, in Korea. H. pylori infection initiates inflammation by induction of interleukin-8 through type IV secretion of CagA. It was recently suggested that induction failure of IL-8 is not associated with defect in cag PAI but associated with cagE locus diversity. This study was designed to investigate ability of 11-8 in-duction according to sequence variation within the cagE gene, cagA TP motifs and vacA m-types in vitro study using AGS cell-line, and to evaluate its association with different clinical outcome. Seventy-four H. pylori stains were isolated from 23 patients with gastric cancer (Ca), 24 subjects with gastritis (G) and 27 patients with duodenal ulcer (Du) in Kangnam St. Mary's Hospital, Seoul, Korea. cagE gene diversity was confirmed by the PCR-RFLP methods with MboI/NlaIII and tyrosine phosphate motifs (TPMs) of cagA was determined TPM-A and C by using DdeI/Tsp5091 restriction enzyme and TPM-B was determend by Real time PCR the method of Owen et al. and IL-8 was measured by ELISA assay. IL-8 activity was positively detected in 59 among 74 strains $(79.7\%)$. IL-8 secretion was significantly increased in MboI A and MboI B type compared to MboI C type and in MboI/NlaIII A-C and B-C type than C-C type. 1L-8 activity was not associated with either the number or composition of cagA tyrosine phosphorylation motifs and vacA m-type. There was no significant difference in IL-8 activity among patient groups. cagE gene diversity is thought to be mainly associated with the induction of IL-8 in H. pylori infection.

• Childhood Kidney Diseases
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• v.4 no.1
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• pp.69-76
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• 2000

Purpose: The Pathogenesis of primary noctllrnal enuresis(PNE) is still controversial. Genetic factor and maturational delay of micturition reflex including arousal disorder, lack of nocturnal Arginine Vasopressin(AVP) release and functional bladder capacity have been suggested. We analyzed the risk factors of PNE. Methods: Fifty five children with PNE (20 enuretics diagnosed at school physical examination of the first grade students at Mok-Dong Elementary School and 35 enuretics (Age 6-7 year) diagnosed at Ewha Womans University Mok Dong Hospital) and 221 control students without PNE at school physical examination were included. Genetic, stress and developmental factors, arousability, water intake, urine volume, maximun voiding volume and daytime voiding dysfunction were compared. Results: 1) There was no significant difference between PNE and control group in sex ratio, birth order, percentage of working mothers, parental and child personality, age to start walking, school record and duration of sleep. 2) Family history in the PNE group was significantly higher than control group ($20.0\%\;vs\;2.7\%$)(P<0.05). 3) The difficulty in arousal in the PNE group was significantly more common than the control group ($70.9\%\;vs\;54.3\%$)(P<0.05). 4) Nocturnal water intake in the PNE group was significantly greater than the control group ($330{\pm}158.2\;mL\;vs\;235{\pm}129.5\;mL$). Nocturnal urine volume in the PNE group was significantly greater than the control group ( $390{\pm}61.5\;mL\;vs\;140{\pm}43.2\;mL$)(P<0.05). Daily water intake and daily urine volume did not significantly differ between the two groups. 5) Maximum urine volume per void in the PNE group was significantly lower than the control group ($107{\pm}35.9\;mL\;vs\;236{\pm}41.3\;mL$). Daytime voiding dysfunction in the PNE group was significantly more common than the control group ($80.0\%\;vs\;57.9\%$). The voiding frequency in the PNE group was significantly greater than the control group ($7.0{\pm}3.6\;vs\;5.4{\pm}1.6$)(P<0.05). Conclusion: In addition to genetic factors and maturational delay of micturition reflex (difficulty in arousal, nocturnal polyuria and decreased functional bladder capacity) nocturnal polydypsia was found to be the important risk factors fur PNE. So nocturnal fluid restriction should be encouraged as the first-line management of PNE.