• Nuclear Engineering and Technology
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• v.53 no.9
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• pp.3068-3084
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• 2021

Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to experimentally assess the damage and vibrations of NPP buildings subjected to aircraft crash. In present Part I, two shots of reduce-scaled model test of aircraft impacting on NPP building were carried out. Firstly, the 1:15 aircraft model (weighs 135 kg) and RC NPP model (weighs about 70 t) are designed and prepared. Then, based on the large rocket sled loading test platform, the aircraft models were accelerated to impact perpendicularly on the two sides of NPP model, i.e., containment and auxiliary buildings, with a velocity of about 170 m/s. The strain-time histories of rebars within the impact area and acceleration-time histories of each floor of NPP model are derived from the pre-arranged twenty-one strain gauges and twenty tri-axial accelerometers, and the whole impact processes were recorded by three high-speed cameras. The local penetration and perforation failure modes occurred respectively in the collision scenarios of containment and auxiliary buildings, and some suggestions for the NPP design are given. The maximum acceleration in the 1:15 scaled tests is 1785.73 g, and thus the corresponding maximum resultant acceleration in a prototype impact might be about 119 g, which poses a potential threat to the nuclear equipment. Furthermore, it was found that the nonlinear decrease of vibrations along the height was well reflected by the variations of both the maximum resultant vibrations and Cumulative Absolute Velocity (CAV). The present experimental work on the damage and dynamic responses of NPP structure under aircraft impact is firstly presented, which could provide a benchmark basis for further safety assessments of prototype NPP structure as well as inner systems and components against aircraft crash.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.206-211
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• 2021

Hygienic behavior of Honey bees, Apis mellifera, was evaluated by uncapping and removing ability of dead broods from the nest. Hygienic behavior is originated from quantitative traits, which are expected to express key roles in colony defense against mite parasites and bacterial and fungal diseases. It is regarded as one of important characteristics of honey bee's resistance to parasites and pathogens. In this study, five inbreed and two hybrid lines of A. mellifera, the former five inbreed lines, which have been reared for over eight years at the National Academy of Agricultural Science in Korea, and the latter two hybrid lines, which have been bred by crossing between the inbreed lines, were investigated on their hygienic behavior by a pin-killed brood assay at 12hrs and 24hrs after treatment. The results indicated that after 12hrs one inbred line was proved to be hygienic (removal rate of dead brood >90%), three inbred and two hybrid lines showed intermediate behavior, and one inbred line belonged to non-hygienic (removal rate of dead brood <70%). However, after 24hrs, only one line was considered to be intermediate as removal rate was below 90%, thus all except this line had shown hygienic behavior.

• Journal of Animal Science and Technology
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• v.61 no.2
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• pp.55-60
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• 2019

Colibacillosis is one of the major health problems in young piglets resulting in poor health and death caused by Escherichia coli producing F18 pili and Shiga toxin 2e. It is pivotal to reduce colibacillosis in weaned piglets to enhance production performance. In this study, we evaluated synbiotics as the gut health improvement agents in the mouse model challenged with Shiga toxin-producing E. coli (STEC) isolated from piglets. Prebiotic lactulose was formulated with each $5.0{\times}10^6CFU/mL$ of Pediococcus acidilactici GB-U15, Lactobacillus plantarum GB-U17, and Lactobacillus plantarum GB 1-3 to produce 3 combinations of synbiotics. A total of 40 three weeks old BALB/c mice were randomly assigned to 4 groups (n = 10): a control group and 3 synbiotics treated groups. Each treatment groups were daily administrated with $5.0{\times}10^6CFU/mL$ of one synbiotics for the first week, and every 3 days during the second week. All the mice were challenged with $8.0{\times}10^8CFU/mL$ of STEC 5 days after animals began to receive synbiotics. Mice treated with synbiotics based on Pediococcus acidilactici GB-U15 and Lactobacillus plantarum GB-U17 significantly improved daily weight gain compared to mice in other groups. While mice treated with GB-U15 showed better fecal index, no significant differences were observed among groups. Gross lesion and histopathological evaluations showed that mice treated with GB-U15 moderately improved recovery from STEC infection. In conclusion, our results suggest that the synbiotics formulated with lactulose and Pediococcus acidilactici GB-U15 have potential benefits to prevent and improve colibacillosis in weaned piglets.

• Journal of the Korean Applied Science and Technology
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• v.39 no.1
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• pp.42-51
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• 2022

This study was conducted to identify the factors affecting the problem solving ability in nursing students. Method: The subjects of this study were 226 nursing students from two universities located in G and C provinces. The collected data were analyzed by t-test, ANOVA, Correlation Coefficient, and Multiple Regression Analysis. Results: As a result of multiple regression analysis, the significant predictors of problem solving ability of nursing students were critical thinking disposition(β=.490, p<.001) and self-directed learning ability(β=.355, p=<.014). Problem solving ability was explained 61.9% of variance in critical thinking disposition and self-directed learning ability. Conclusion: The results of this study showed that self-directed learning ability and critical thinking disposition in nursing students were the influential factor on problem solving ability. Therefore, the results of this study suggest that it is necessary to find ways to improve critical thinking disposition and self-directed learning ability in order to improve problem solving ability of nursing students, and it is considered to be useful as basic data for developing education programs to improve problem solving ability.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1513-1513
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• 2001

Present Food Legislation compels dairy industry to carry out analyses in order to guarantee the food safety and quality of products. Furthermore, in many cases industry pays milk according to bacteriological or/and nutritional quality. In order to do these analyses, several expensive instruments are needed (Milkoscan, Fossomatic, Bactoscan). NIRS technology Provides a unique instrument to deal with all analytical requirements. It offers as main advantages its speed and, specially, its versatility, since not only allows determine all the parameters required in milk analysis, but also allows analyse other dairy products, like cheese or whey. The objective of this study is to develop NIRS calibration equations to predict several quality parameters in goat milk, cheese and whey. Three sets of 123 milk samples, 190 cheese samples and 109 whey samples, have been analysed in a FOSS NIR Systems 6500 I spectrophotometer equipped with a spinning module. Milk and whey were analysed by folded transmission, using circular cells with gold surface and pathlength of 0.1 m, while intact cheese was analysed by reflectance using standard circular cells. NIRS calibrations were obtained for the prediction of chemical composition in goat milk, for fat (r$^2$=0.92; SECV=0.20%), total solids (r$^2$=0.95: SECV=0.22%), protein (r$^2$=0.94; SECV=0.07%), casein (r$^2$=0.93; SECV=0.07%) and lactose (r$^2$=0.89; SECV=0.05%). Moreover, equations have been performed to determine somatic cells (r$^2$=0.81; SECV=276.89%) and total bacteria (r$^2$=0.58; SECV=499.32%) counts in goat milk. In the case of cheese, calibrations were obtained for the prediction of fat (r$^2$=0.92; SECV=0.57), total solids (r$^2$=0.80; SECV=0.92%) and protein (r$^2$=0.70; SECV=0.63%). In whey, fat (r$^2$=0.66; SECV=0.08%), total solids (r$^2$=0.67; SECV=0.19%) and protein (r$^2$=0.76; SECV=0.07%) NIRS equations were obtained. These results proved the viability of NIRS technology to predict chemical and microbiological parameters and somatic cells count in goat milk, as well as chemical composition of goat cheese and whey.

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1206-1212
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• 2023

The Wnt/β-catenin pathway plays essential roles in regulating various cellular behaviors, including proliferation, survival, and differentiation [1-3]. The intracellular β-catenin level, which is regulated by a proteasomal degradation pathway, is critical to Wnt/β-catenin pathway control [4]. Normally, casein kinase 1 (CK1) and glycogen synthase kinase-3β (GSK-3β), which form a complex with the scaffolding protein Axin and the tumor suppressor protein adenomatous polyposis coli (APC), phosphorylate β-catenin at Ser45, Thr41, Ser37, and Ser33 [5, 6]. Phosphorylated β-catenin is ubiquitinated by the β-transducin repeat-containing protein (β-TrCP), an F-box E3 ubiquitin ligase complex, and ubiquitinated β-catenin is degraded via a proteasome pathway [7, 8]. Colorectal cancer is a significant cause of cancer-related deaths worldwide. Abnormal up-regulation of the Wnt/β-catenin pathway is a major pathological event in intestinal epithelial cells during human colorectal cancer oncogenesis [9]. Genetic mutations in the APC gene are observed in familial adenomatous polyposis coli (FAP) and sporadic colorectal cancers [10]. In addition, mutations in the N-terminal phosphorylation motif of the β-catenin gene were found in patients with colorectal cancer [11]. These mutations cause β-catenin to accumulate in the nucleus, where it forms complexes with transcription factors of the T-cell factor/lymphocyte enhancer factor (TCF/LEF) family to stimulate the expression of β-catenin responsive genes, such as c-Myc and cyclin D1, which leads to colorectal tumorigenesis [12-14]. Therefore, downregulating β-catenin response transcription (CRT) is a potential strategy for preventing and treating colorectal cancer. Plant cytokinins are N⁶-substituted purine derivatives; they promote cell division in plants and regulate developmental pathways. Natural cytokinins are classified as isoprenoid (isopentenyladenine, zeatin, and dihydrozeatin), aromatic (benzyladenine, topolin, and methoxytopolin), or furfural (kinetin and kinetin riboside), depending on their structure [15, 16]. Kinetin riboside was identified in coconut water and is a naturally produced cytokinin that induces apoptosis and exhibits antiproliferative activity in several human cancer cell lines [17]. However, little attention has been paid to kinetin riboside's mode of action. In this study, we show that kinetin riboside exerts its cytotoxic activity against colon cancer cells by suppressing the Wnt/β-catenin pathway and promoting intracellular β-catenin degradation.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.5
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• pp.1-13
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• 2007

In this research, we found out that bridging nodes have great effect on the robustness of protein-protein interaction networks. Until now, many researchers have focused on node's degree as node's essentiality. Hub nodes in the scale-free network are very essential in the network robustness. Some researchers have tried to relate node's essentiality with node's betweenness centrality. These approaches with betweenness centrality are reasonable but there is a positive relation between node's degree and betweenness centrality value. So, there are no differences between two approaches. We first define a bridging node as the node with low connectivity and high betweenness value, we then verify that such a bridging node is a primary factor in the network robustness. For a biological network database from Internet, we demonstrate that the removal of bridging nodes defragment an entire network severally and the importance of the bridging nodes in the network robustness.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.104-110
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• 2013

This study assessed hazards at the harvest stage of strawberry farms which may cause risk to humans. A total of 216 samples were collected from 6 strawberry farms (soil culture farms: A, B, C; nutriculture farms: D, E, F) located in Western Gyeongnam. The collected samples were subjected for sanitary indicator bacteria (aerobic plate count, coliforms and Escherichia coli), major foodborne pathogens (E. coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus and Bacillus cereus), and fungi. The levels of APC and coliform in the soil culture farms were 1.0-6.9 and 0.4-4.6 log CFU/g (leaf, mL, hand or 100 $cm^2$), respectively. The samples obtained from the nutriculture farms were contaminated with the levels of 0.8-4.9, and 0.2-2.6 log CFU/g (leaf, mL, hand or 100 $cm^2$) of APC and coliform. However, E. coli was not detected in any samples. In major foodborne pathogens, S. aureus was detected at the level of ${\leq}$3.3 log CFU/hand in workers' hand samples and B. cereus was detected at the levels of 0.4-4.1 log CFU/g (hand or 100 $cm^2$) in soil, plants and workers' hygiene. L. monocytogenes, E. coli O157:H7 and Salmonella spp. were not detected. Fungi were detected at the levels of 1.0-5.2 and 0.2-4.4 log CFU/g (leaf, mL, hand or 100 $cm^2$) in soil culture and nutriculture farms, respectively.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.353-365
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• 2023

The effects of climate change on green infrastructure and environmental media remain uncertain and context-specific despite numerous climate projections globally. In this study, the extreme weather conditions in seven major cities in South Korea were characterized through statistical analysis of 20-year daily meteorological data extracted fro m the Korea Meteorological Administration (KMA). Additionally, the impacts of extreme weather on Nature-based Solutions (NbS) were determined through a comprehensive review. The results of the statistical analysis and comprehensive review revealed the studied cities are potentially vulnerable to varying extreme weather conditions, depending on geographic location, surface imperviousness, and local weather patterns. Temperature extremes were seen as potential threats to the resilience of NbS in Seoul, as both the highest maximum and lowest minimum temperatures were observed in the mentioned city. Moreover, extreme values for precipitation and maximum wind speed were observed in cities from the southern part of South Korea, particularly Busan, Ulsan, and Jeju. It was also found that extremely low temperatures induce the most impact on the resilience of NbS and environmental media. Extremely cold conditions were identified to reduce the pollutant removal efficiency of biochar, sand, gravel, and woodchip, as well as the nutrient uptake capabilities of constructed wetlands (CWs). In response to the negative impacts of extreme weather on the effectiveness of NbS, several adaptation strategies, such as the addition of shading and insulation systems, were also identified in this study. The results of this study are seen as beneficial to improving the resilience of NbS in South Korea and other locations with similar climate characteristics.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1014-1024
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• 2010

Pepper ($Capsicum$ spp.) anthracnose caused by $Colletotrichum$ $acutatum$ is a destructive disease susceptible to areas where chili peppers are grown. $Capsicum$ $baccatum$ var. $pendulum$ (Cbp) is resistant to anthracnose and has actively been used for interspecific hybridization for the introgression of resistance gene(s) into cultivated chili peppers. The goals of this study were to determine the inheritance of resistance to anthracnose within $Capsicum$ $baccatum$ and to map quantitative trait loci (QTLs) for the anthracnose resistance. A genetic mapping population consisting of 126 $F_2$ plants derived from a cross between $Capsicum$ $baccatum$ var. $pendulum$ (resistant) and $Capsicum$ $baccatum$ 'Golden-aji' (susceptible) was used for linkage mapping. The linkage map was constructed with 52 SSRs, 175 AFLPs, and 100 SRAPs covering 1,896cM, with an average interval marker distance of 4.0cM. Based on this map, the number, location, and effect of QTLs for anthracnose resistance were studied using plants inoculated in the laboratory and field. A total of 19 quantitative trait loci (2 major QTLs and 16 minor QTLs) were detected. Two QTLs ($An8.1$, $An9.1$) showed 16.4% phenotypic variations for anthracnose resistance after wounding inoculation. In addition, five minor QTL loci ($An7.3$, $An7.4$, $An4.1$, $An3.1$, $An3.2$) showed a total of 60.73% phenotypic variations of anthracnose resistance in the field test. Several significant QTLs were also detected and their reproducibility was confirmed under different inoculation conditions. These QTLs are now being confirmed with different breeding populations. Markers tightly linked to the QTLs that are reliable under different environmental conditions will help to determine the success of marker-assisted selection for anthracnose -resistant breeding programs in chili pepper.