• Proceedings of the Korean Society of Sericultural Science Conference
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• 1997.06a
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• pp.73-101
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• 1997

Baculoviruses are characterized by large double-stranded circular DNA genomes and rod-shaped enveloped virions. Bombyx mori nucleopolyhedrovirus(BmNPV) is a major pathogen, which causes severe damage in sericulture. Currently, BmNPV is recogtnized as an improtant tool in molecular biology, especially for expression of useful genes in B.mori cells and silkworm larvae. Our laboratories have focused on the studies of the molecular mechanisms of BmNPV replication and the application of BmNPV to agriculture and medicine. The entire nucleotide sequence of the BmNPV genome has recently determined. The BmNPV genome possessed 135 putative genes and 7 homologous repeated sequence (hrs) regions. Relatively little space, a few to a few hundred base-pairs, was observed between the open reading frames and hrs. Termination codons often overlapped. These results showed a compactly packde BmNPV genome. Based on comparative sequence analyses, we speculated that the ancestor of BmNPV was a baculovirus similar to Autographa californica NPV(AcNPV). The function of the BmNPV genes were characterized by gene deletion analysis; p35 was found to be involved in blocking apoptosis and cysteine proteinase was found to be involved in horizontal virus transmission by degrading viral-infected larval host. By AcNPV and BmNPV coinfection experiments, we identified a BmNPV gene involved in expanding host specificity of AcNPV. The identified gene was likely encoded a DNA helicase based on the amino acid sequence analysis; a few amino acid substitutions in the putative DNA helicase gene resulted in the expansion of host range of AcNPV. These findings indicate that BmNPV evolved within a short period from an AcNPV-like ancestral virus due to rapid evolution including specific amino acid substitutions and gene deletions/insertions.

• Elastomers and Composites
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• v.54 no.2
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• pp.110-117
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• 2019

The characterization of the ozone oxidation for raw natural rubber (NR) was investigated under controlled conditions through image and fourier transform infrared (FT-IR) analysis. The ozone oxidation was performed on a transparent thin film of raw NR coated on a KBr window in a dark chamber at $40^{\circ}C$ under low humidity conditions to completely exclude thermal, moisture, or light oxidation. The ozone concentration was set at 40 parts per hundred million (pphm). Before or after exposure to ozone, the image of the thin film for raw NR was observed at a right or tilted angle. FT-IR absorption spectra were measured in the transmission mode according to ozone exposure time. The ozone oxidation of NR was determined by the changes in the absorption peaks at 1736, 1715, 1697, and $833cm^{-1}$, which were assigned to an aldehyde group (-CHO), a ketone group (-COR), an inter-hydrogen bond between carbonyl group (-C=O) from an aldehyde or a ketone and an amide group (-CONH-) of protein, and a cis-methine group ($is-CCH_3=CH-$, respectively. During ozone exposure period, the results indicated that the formation of the carbonyl group of aldehyde or ketone was directly related to the decrement of the double bond of cis-1,4-polyisoprene. Only carbonyl compounds such as aldehydes or ketones seemed to be formed through chain scission by ozone. Long thin cracks with one orientation at regular intervals, which resulted in consecutive chain scission, were observed by image analysis. Therefore, one possible two-step mechanism for the formation of aldehyde and ketone was suggested.

• Korean Journal of Heritage: History & Science
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• v.35
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• pp.320-343
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• 2002

In Seoul city, The maul-gut(마을굿) called bugundang-gut(부군당굿) have been transmitted by people lived on the banks of han-river. The purpose of this document is to make a study the present meaning of bugundang-gut that have been transmitted in metropolitan city. The bugundang-gut was the official ritual in a government office during the Chosun dynasty. However, the bugundang-gut had been spread along kyunggang(경강, Han-river in Seoul) in the late Chosun period. At that times, the population kyunggang area was increased with the inflow of outside population and the commercial destrict was extended to many district along kyunggang. The main points of this study are as follows. Firstly, I investigate that bugundang-gut have been transmitted by a Seoulite to the backbone. They are the main body of bugundang-gut transmitting from generation to generation. Secondly, I study about nami-janggun-sadangje(남이장군사당제) appointed to seoul city immaterial cutural properties. It is a kind of bugundang-gut. So namijanggun-sadangje was appointed to seoul city immaterial cutural properties, as it was supported by a local autonomous entity. Thirdly, I investigate a plan that can be handed down an offspring in seoul city. We must revise the cultural properties system like that of Japan. Even though many bugundang-gut isn't appointed to cutural propertie except nami-janggun-sadangje, we must recognize their importance and keep a record character of bugundang-gut by investigation in detail. Fourthly, I think that bugundang-gut must be developed a regional public holiday. If it is developed a regional public holiday, many young person can be take part in bugundang-gut.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.45-54
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• 2019

In this study, we analyze the rattle noise of a power takeoff (PTO) driveline and develop a PTO driveline resonance model. We measured the rattle noise of the PTO driveline on the output shaft and, by analyzing the rattle noise in the time domain, we determine that the engine expansion stroke period matches the sound pressure of rattle noise. This finding helped us demonstrate that the rattle noise is caused by the collision between the PTO driving gear and the gear driven by the engine expansion stroke; the torsional vibration caused by this collision is affected by the angular velocity fluctuation of the PTO drive shaft. By measuring the angular velocity of the PTO drive shaft, we confirm that the angular velocity fluctuation of the engine flywheel tends to excessively amplify the PTO drive shaft angular velocity fluctuation. We conclude that the resonance, which occurs when the operating frequency of the engine is close to the natural frequency of the tractor power transmission system, causes the excessive angular velocity fluctuation of the PTO drive shaft. We performed a modal analysis of the PTO driveline resonance and, using the characteristic equation, we show that the resonance occurs when the engine rotation speed is close to 850 rpm, which matches the natural frequency of the PTO driveline.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.696-703
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• 2019

Cronobacter sakazakii is an opportunistic pathogen causing serious infections in neonates. In this study, a bacteriophage ${\Phi}CS01$, which infects C. sakazakii, was isolated from swine feces and its morphology, growth parameters, and genomic analysis were investigated. Transmission electron microscopy revealed that ${\Phi}CS01$ has a spherical head and is 65.74 nm in diameter with a 98.75 nm contracted tail, suggesting that it belongs to the family Myoviridae. The major viral proteins are approximately 71 kDa and 64 kDa in size. The latent period of ${\Phi}CS01$ was shown to be 60 min, and the burst size was 90.7 pfu (plaque-forming units)/infected cell. Bacteriophage ${\Phi}CS01$ was stable at $4-60^{\circ}C$ for 1 h and lost infectivity after 1 h of heating at $70^{\circ}C$. Infectivity remained unaffected at pH 4-9 for 2 h, while the bacteriophage was inactivated at pH <3 or >10. The double-stranded ${\Phi}CS01$ DNA genome consists of 48,195 base pairs, with 75 predicted open reading frames. Phylogenetic analysis is closely related to that of the previously reported C. sakazakii phage ESP2949-1. The newly isolated ${\Phi}CS01$ shows infectivity in the host bacterium C. sakazakii, indicating that it may be a promising alternative to antibacterial agents for the removal of C. sakazakii from powdered infant formulas.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.4
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• pp.453-461
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• 2019

In this paper, we focus on the study of multi-node rendezvous on one common channel among multiple channels before transmitting in CRAHNs (Cognitive Radio Ad-hoc Networks) for the efficient use of inefficient frequency resources. Most existing researches have dealt with the channel rendezvous between two nodes. But, it can be time-consuming to apply them to three or more nodes. In addition, it cab be impossible to communicate with each other. Therefore, in this paper, we propose a Multi-Node Sequence (MNSEQ), which allows three or more nodes to rendezvous on a single common channel in a short period of time. And, CSMA/CA was applied for data exchange after rendezvous. By performance evaluation through very extensive simulations, we have demonstrated that the proposed MNSEQ outperforms the existing scheme in terms of communication completion time and transmission efficiency.

• Entomological Research
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• v.48 no.6
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• pp.522-532
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• 2018

As the vector-borne diseases rapidly increased due to climate change, we investigated the incidence of flavivirus occurrence among female mosquito species in urban and rural study sites in Daegu and Gunwi, South Korea using Realtime PCR. We collected more individuals and more species of mosquito in 2016 than in 2015. In 2015, we recorded a total of 22,033 mosquitoes (Trap Index, 224.8) representing 10 species from 5 genera, whereas in 2016, a total of 27,137 mosquitoes (Trap Index, 278.7) representing 13 species from 6 genera were collected. The number of mosquitoes in 2016 was higher in all study sites, except in the migratory bird habitats where the number decreased. Of the 14 species collected over the two years, Aedes vexans nipponii and Anopheles spp. were dominant in the cowsheds in rural farmland; Culex pipiens complex, in urban residential areas; and, Anopheles spp. and Cu. pipiens complex in migratory bird habitats caught in a black light trap. Cu. pipiens complex and Ae. albopictus in urban parks and Ae. albopictus and Armigeres subalbatus in migratory bird habitats were the dominant species caught in BG-sentinel traps. We found that the number of mosquitoes was highest during July-September. We analyzed 1,725 pools to detect flavivirus, where Chaoyang virus was detected among Ae. vexans niponii collected from cowsheds in rural farmland in 2016. The increased number of mosquitoes recorded in 2016 was mainly due to increased temperatures in the study areas, and reflected the change in study sites.

• Journal of Veterinary Science
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• v.19 no.6
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• pp.750-758
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• 2018

Influenza virus infection is a zoonosis that has great socioeconomic effects worldwide. Influenza infection induces respiratory symptoms, while the influenza virus can infect brain and leave central nervous system sequelae. As children are more vulnerable to infection, they are at risk of long-term neurological effects once their brains are infected. We previously demonstrated that functional changes in hippocampal neurons were observed in mice recovered from neonatal influenza infection. In this study, we investigated changes in myelination properties that could affect neural dysfunction. Mice were infected with the influenza virus on postnatal day 5. Tissues were harvested from recovered mice 21-days post-infection. The expression levels for myelin basic protein (MBP) were determined, and immunohistochemical staining and transmission electron microscopy were performed. Real-time polymerase chain reaction and Western blot analyses showed that mRNA and protein expressions increased in the hippocampus and cerebellum of recovered mice. Increased MBP-staining signal was observed in the recovered mouse brain. By calculating the relative thickness of myelin sheath in relation to nerve fiber diameter (G-ratio) from electron photomicrographs, an increased G-ratio was observed in both the hippocampus and cerebellum of recovered mice. Influenza infection in oligodendrocyte-enriched primary brain cell cultures showed that proinflammatory cytokines may induce MBP upregulation. These results suggested that increased MBP expression could be a compensatory change related to hypomyelination, which may underlie neural dysfunction in recovered mice. In summary, the present results demonstrate that influenza infection during the neonatal period affects myelination and further induces functional changes in influenza-recovered mouse brain.

• Journal of Genetic Medicine
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• v.17 no.2
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• pp.73-78
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• 2020

Purpose: Congenital myasthenic syndrome (CMS) is a clinically and genetically heterogeneous group of disorders characterized by impaired neuromuscular transmission. This study aims to provide the clue for early diagnosis and improved therapeutic strategies in CMS. Materials and Methods: Through the targeted panel sequencing including twenty CMS causative genes, eleven patients were genetically confirmed and enrolled in this study. A retrospective medical record review was carried out for the clinical and laboratory data analysis. Results: The age of patients ranged from 5 to 23 years, with the median age of 16 years. The peak age at onset of symptoms was the neonatal period. Seven out of the eleven patients were symptomatic at birth. The most commonly reported initial finding was generalized hypotonia with poor sucking and crying. Mean time to accurate diagnosis was 9.3±5.0 years. Total fifteen different variants in seven genes associated with CMS (DOK7, AGRN, RAPSN, CHRNE, COLQ, SLC5A7, and GFPT1) were identified. Conclusion: We describe the clinical and genetic characteristics of CMS patients and treatment outcome in a single tertiary center. High clinical suspicion and timely molecular diagnosis is particularly important for the tailored therapy to maximize clinical improvement in CMS.

• Journal of the Daesoon Academy of Sciences
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• v.34
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• pp.141-169
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• 2020

This study focuses on the interpretation and transformation of "The Great Learning" within the Korean new religion, Daesoon Jinrihoe. Joseon Dynasty Korea was a member of the Chinese Character Cultural Sphere in East Asia. The examination and recruitment system of the Yuan Dynasty influenced the Joseon Dynasty for a long historical period. Zhu Xi's (朱熹) version of The Four Books were accepted and applied in imperial examinations during the Joseon Dynasty. The 18th century Confucian thinker, Jeong Yak-Yong (丁若鏞), overturned and rebuilt his own system for studying and interpreting The Four Books (四書學). Zhu Xi and Jeong Yak-Yong's systems of thought influenced Confucianism knowledge in that era. The historical figure deified as the Supreme God by Daesoon Jinrihoe, Kang Jeungsan (姜甑山), was trained in the study of The Four Books within that cultural and philosophical context, and this is especially evident in his interpretation and transmission of "The Great Learning." Kang Jeungsan regarding The Great Learning as deeply important. That text combined Confucian discourse on Principle, Mind, and Practice. In his interpretation, The Great Learning was also a medical and religious book that had holy and mysterious powers. In Mugeuk-do and Taegeuk-do (direct predecessors to Daesoon Jinrihoe), Jo Jeongsan interpreted the concept of Sincerity and Regularizing the Mind and incorporated them into doctrine as 'Sincerity, Respectfulness, and Faithfulness' and 'Guarding against Self-deception.' Park Wudang practiced and spread those doctrines to Korea, and Daesoon Jinrihoe devotees continue to follow those doctrines in present times.