• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.353-355
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• 2000

The seasonal occurrence of aphids was investigated in the soybean Held to increase the control efficiency of aphid vectors of Soybean Mosaic Virus. The patterns of aphids occurrence were different according to planting time. There were two peaks in late June and mid-August in aphid population in optimum seeding (May 20), whereas the peak was around mid-June in early seeding(Apr, 20). Acyrthosiphon solani was dominant Species in early seeding, while Aphis glycines was dominant in optimum seeding. In early seeding, SMV incidence increased rapidly between 20 June and 30 June, suggesting that virus spread was strongly correlated with increased colonization of aphids. Imidacloprid WP, benfuracarb EC and acephate WP showed a good effect for the control of aphids without phytotoxicity. In the plot with infurrow treatment of imidachloprid G until 52 days after shooting, aphids were controled effectively. Acephate WP was applied as a foliar spray at V4, V6, or V4/V6 stage and all the treatments were effective on reducing: SMV incidence.

• Korean Journal of Veterinary Research
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• v.52 no.4
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• pp.213-221
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• 2012

A total of 18 Newcastle disease virus (NDV) isolates that were recovered from 1949 through 1997 were characterized and pathotyped. All viruses were highly virulent as determined by intracerebral pathogenicity indices ${\geq}1.81$ in day-old. These pathotypes are typical for viscerotropic velogenic NDV (VVNDV) pathotype viruses. Some differences were observed for the chicken red blood cell elution rate and thermostability of the hemagglutinin at $56^{\circ}C$. Three antigenic groups were identified by a hemagglutination-inhibition assay using NDV monoclonal antibodies. And the predominant gross lesions were as follows: discharge from the nasal cavity, tracheal mucus, petechial hemorrhage in the heart fat, kidney urates and hemorrhage with or without necrosis in the gastrointestinal tract. Severe hemorrhagic or necrotic lesions were also noted in the lymphoid organs and were localized primarily in the spleen and cecal tonsil. However, differences in the occurrence and frequency of the gross lesions were observed between the virus strains. Among them, NDV strains that induced neurological symptoms belonged only to genotype VI. This strain had spread throughout Korea during the late 1980s to the 1990s, which suggests that specific VVNDVs genotypes might result in neurological symptoms.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.350-354
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• 2008

In order to investigate the prevalence of sexually transmitted viruses such as human papillomavirus (HPV) and herpes simplex virus (HSV) in Korean commercial sex workers (CSWs), we selected 188 CSWs (age range 20-44 years, median age 24 years) who regularly visited one public health center in Seoul, Korea. HPV genotypes were analyzed by using a HPV DNA Chip, and an enzyme-linked immunosorbent assay (ELISA) was used to detect type-specific IgG against HSV2 antibody identifying seropositivity for HSV2 infection. Polymerase chain reaction (PCR) was performed with specific primers to detect HPV and HSV1/2 in cervical swabs from the CSWs. The prevalence of HPV infection was 83.5% in 188 cervical swab specimens and the main high-risk HPV genotypes were HPV16, 18, 56, and 58. The principal low-risk HPV genotypes were HPV6 and 11. The prevalence of HSV1/2 DNA was 13.8% and HSV2 seroprevalence was 86.2%. These results suggest that high frequencies of HPV and HSV2 infection might contribute to the rapid spread of STD viruses in CSWs in Korea. Additionally, an understanding of why high-risk HPV genotypes are so prevalent could provide guidelines for prophylactic vaccine development in Korea.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.315-323
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• 2009

Foot-and-mouth disease (FMD) virus exists in seven serotypes and is known to be a highly contagious disease that is hard to eradicate from the world. The O, A, Asia1 and SAT2 serotypes commonly infected cattle, sheep and goats during 2007~2009 throughout the world. In particular, the outbreak of the Asia1 serotype in China appeared in all areas from 2005 and is still present. Surprisingly, in 2009, Taiwan reported the first outbreak of the type O serotype since 2001. Then type A appeared in China for the first time since the early 1960s. The virus shows a close relationship to the viruses from Southeast Asia suggesting one or more recent introductions into China in the OIE reports. Recently the subtype of A/Iran05 spread to nearby countries exhibiting genomic evolution. The use of molecular epidemiology is an important tool in understanding and consequently controlling the FMD virus. The phylogenetic analysis with VP1 gene was especially useful for molecular epidemiological studies and showed the same pattern which matches with serotype classification. This paper describes basic information about the disease, and the serotype-specific characteristics and evolution to perform molecular epidemiological analysis. Furthermore, we show the importance of the genetic evolution on the FMD serotypes in global surveillance and molecular epidemiology of FMD for outbreak investigation.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.1-7
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• 2002

Recently, the rabies cases have been reported in Paju- and Yangju-gun, Gyeonggj province near Seoul metropolitan area. The Pukhansan national park, nearly located from the cities, is suspected to be a high risk area for incidence and spread of the rabies to metropolitan area. This study was conducted to investigate the prevalence rate for rabies antibody of dogs near the Pukhansan national park and in some other districts in Seoul metropolitan city. From march to october 2001, a total of 306 serum samples were taken from dogs for breeding(189) md pet dogs(117) in 4 districts near the Pukhansan national park and other districts of Seoul. Rabies virus antibodies in sera were detected by neutralizing peroxidase - linked as say (NPLA). Of the 306 sera of dogs tested, 74 (24.2%) were positive to rabies virus antibody. The prevalence rates of rabies antibody in Pukhansan national park area and in the other districts of Seoul city were 23.7% and 25.3%, respectively There was no significant difference in the prevalence rate between these two districts. The prevalence rates of rabies antibody in pet dogs and dogs for breeding were 40.2% and 14.3% respectively. The prevalence rates of rabies antibodies in less than 1 year, 1∼<2 years, 2∼<3 years, and over 3 years old dogs were 14.5%, 22.4%, 32.6%, and 27.1%, respectively, and overall 24.2% in the dog population. In addition, we found that dogs less than 1 year old had lower antibody prevalence than those over 1 year old. It was concluded that enhancement of vaccination is important in the prevention of the rabies, and that rabies vaccines should not be less supplied than the population of the dog.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.377-382
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• 2012

This study investigated the occurrence of sweet potato whitefly, Bemisia tabaci affecting cucumber, eggplant and red pepper, as well as sweet potato species, and its response to insecticides in Gyeonggi province from 2010 to 2011. Sweet potato whitefly is widespread throughout the southern part of Gyeonggi province. Most regional populations of B. tabaci belong to biotype Q having been reported in the south Korea since 2005, but in Goyang mixed populations of two biotypes (B and Q) were found. Survey results of Tomato Yellow Leaf Curl Virus (TYLCV) disease that was vectored by B. tabaci indicated that this virus disease was not spread throughout the Gyeonggi province. Biotype Q of B. tabaci was found to be resistant to neonicotinoid insecticides, whereas biotype B was highly susceptible to them.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1398-1403
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• 2016

The simultaneous detection and accurate identification of hepatitis A virus (HAV) is critical in food safety and epidemiological studies to prevent the spread of HAV outbreaks. Towards this goal, a one-step duplex reverse-transcription (RT)-PCR method was developed targeting the VP1/P2B and VP3/VP1 regions of the HAV genome for the qualitative detection of HAV. An HAV RT-qPCR standard curve was produced for the quantification of HAV RNA. The detection limit of the duplex RT-PCR method was 2.8 × 10¹ copies of HAV. The PCR products enabled HAV genotyping analysis through DNA sequencing, which can be applied for epidemiological investigations. The ability of this duplex RT-PCR method to detect HAV was evaluated with HAV-spiked samples of fresh lettuce, frozen strawberries, and oysters. The limit of detection of the one-step duplex RT-PCR for each food model was 9.4 × 10² copies/20 g fresh lettuce, 9.7 × 10³ copies/20 g frozen strawberries, and 4.1 × 10³ copies/1.5 g oysters. Use of a one-step duplex RT-PCR method has advantages such as shorter time, decreased cost, and decreased labor owing to the single amplification reaction instead of four amplifications necessary for nested RT-PCR.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.20.1-20.13
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• 2021

Background: Pseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear. Objectives: Our study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection. Methods: Kunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi. Results: At 10⁵-10⁶ TCID₅₀ PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRV-infected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 10² TCID₅₀ of PRV produced a significant inflammatory mediator increase. Conclusions: An inflammatory model induced by PRV infection was established in mice, and 10² TCID50 PRV was considered as the best concentration for the establishment of the model.

• The Korean Journal of Emergency Medical Services
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• v.24 no.3
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• pp.161-169
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• 2020

Purpose: This study aims to identify changes in patients' transport time and chief complaints visiting the emergency room via emergency medical services from the "pre-COVID-19 period" compared to the "COVID-19 early-stage period". Methods: This retrospective observational study analyzed the emergency medical services reports at two time periods defined by the COVID-19 virus outbreak in Korea. The study was conducted in Busan, the Republic of Korea, from January 19 through May 6, 2019. Results: The transfer time of patients transported during the "COVID-19 early-stage period" was significantly delayed compared to the "pre-COVID-19 period" (p<.05). We found a significant increase in transport time for patients complaining of respiratory infections compared to patients without symptoms (p<.05). During the "COVID-19 early-stage period", there was a significant increase in the number of patients with respiratory infections and patients complaining of general symptoms compared to the "COVID-19early-stage period" (p<.05). Conclusion: The spread of the COVID-19 virus infection delayed patient transport and increased the number of patients reporting respiratory infection symptoms. Emergency medical services will need administrative and economic support to transport the increased number of patients requiring services.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.27-33
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• 2021

The whole world now is dealing with Coronavirus, and it has turned to be one of the most widespread and long-lived pandemics of our times. Reports reveal that the infectious disease has taken toll of the almost 80% of the world's population. Amidst a lot of research going on with regards to the prediction on growth and transmission through Symptomatic carriers of the virus, it can't be ignored that pre-symptomatic and asymptomatic carriers also play a crucial role in spreading the reach of the virus. Classification Algorithm has been widely used to classify different types of COVID-19 carriers ranging from simple feature-based classification to Convolutional Neural Networks (CNNs). This research paper aims to present a novel technique using a Random Forest Machine learning algorithm with hyper-parameter tuning to classify different types COVID-19-carriers such that these carriers can be accurately characterized and hence dealt timely to contain the spread of the virus. The main idea for selecting Random Forest is that it works on the powerful concept of "the wisdom of crowd" which produces ensemble prediction. The results are quite convincing and the model records an accuracy score of 99.72 %. The results have been compared with the same dataset being subjected to K-Nearest Neighbour, logistic regression, support vector machine (SVM), and Decision Tree algorithms where the accuracy score has been recorded as 78.58%, 70.11%, 70.385,99% respectively, thus establishing the concreteness and suitability of our approach.