• Journal of Environmental Health Sciences
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• v.44 no.1
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• pp.31-43
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• 2018

Objectives: Effective genetic toxicology and molecular biology research techniques and strategies that are highly correlated with the carcinogenic inhalation toxicity test and related research are required. The aim of this study was to maximize the utilization of chemical substances to prevent workers' occupational diseases. Methods: We surveyed the literature, domestic and international references, and the status of relevant domestic and foreign professional organizations. Expert advisory opinions were reflected, and experts were consulted by participating in domestic and overseas academic conferences. Results: The current status of domestic and international genotoxic toxicity evaluation was examined through various documents from related organizations. Cell models for in vitro lung toxicology were investigated and summarized, and the human resources and performance results of genetic toxicity studies and pilot projects were compared and analyzed by holding an advisory meeting. We examined domestic and international genotoxicity guidelines and investigated new test methods for the development of genotoxicity and carcinogenicity. Ultimately, we described long-term future predictions, including the implementation of our researchers' recommendations and occupational genetic toxicology forecasts for future worker health protection. Conclusions: This research project aims to establish current genetic toxicology and molecular biology research techniques and strategies that can maximize the linkage with the carcinogenic inhalation toxicity test and research in the future. We expanded the study of genetic toxicity and establish a foundation forgenetic toxicity in accordance with research trends in Korea and abroad.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.1051-1065
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• 2021

Recent times have seen sustained increases in genetically modified (GM) crops not only for cultivation but also for the utility of food and feed worldwide. Domestically, commercial planting and the accidental or unintentional release of living modified (LM) crops into the environment are not approved. Many detection methods had been devised in an effort to realize effective management of the safety of agricultural genetic resources. In order to develop event-specific polymerase chain reaction (PCR) markers for LM crops, we analyzed the genetic information of LM crops. Genetic components introduced into crops are of key importance to provide a basis for the development of detection methods for LM crops. To this end, a total of 18 varieties from four major LM crop species (maize, canola, cotton, and soybeans) were subjected to an analysis. The genetic components included introduced genes, promoters, terminators and selection markers. Thus, if proper monitoring techniques and single or multiplex PCR strategies that rely on selection markers can be established, such an accomplishment can be regarded as a feasible solution for the safe management of staple crop resources.

• Journal of the Korean Geotechnical Society
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• v.21 no.4
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• pp.115-122
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• 2005

In this paper, a new method composed of discrete element method and genetic algorithm has been introduced to estimate the safety factor and search critical slip surface on slope stability analysis. In case of estimating the safety factor, conventional methods of slope analysis based on the limit equilibrium do not satisfy the overall equilibrium condition; they must make assumptions regarding the inclination and location of the interstice forces. An alternative slope analysis method based on the discrete element method, which can consider the compatibility condition between force and displacement, is presented. Real-coded genetic algorithm is applied to the search for the minimum factor of safety in proposed analysis method. This search method is shown to be more robust than simple optimization routines, which are apt to find local minimum. Examples are also shown to demonstrate the applicability of the proposed method.

• Korean Journal of Veterinary Service
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• v.46 no.3
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• pp.193-202
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• 2023

Porcine epidemic diarrhea is an infectious intestinal disease caused by the porcine epidemic diarrhea virus (PEDV). Especially, when suckling piglets are infected, the mortality rate is close to 100%. PEDV is classified into G1 and G2 types based on genetic differences. The G2 type PEDV outbreak in the United States in 2013 was highly pathogenic and contagious, and it has spread worldwide and caused continuous economic losses. Most commercial vaccines used are G1 type vaccines, and existing vaccines do not fully protect piglets due to genetic differences. In this study, we evaluated the safety of the newly developed G2 type attenuated HSGP vaccine strain by inoculating it into piglets and testing whether the vaccine virus spreads to the non-vaccinated, negative pigs and whether the vaccine reverts to its virulence during serial passage experiments. Each experiment lasted for 7 days for each passage, and fecal viral titers, clinical symptoms, and weight gain were measured daily. After the experiment, necropsy was performed to measure intestinal virus titer and pathological evaluation. As a result of the first passage, no transmission of the vaccine virus to negative pigs co-housed with vaccinated pigs was observed. In addition, after four consecutive passage experiments, the clinical symptoms and small intestine lesions were gradually alleviated, and no virus was detected in the feces in the fourth passage experiment. Therefore, it was concluded that the vaccine was safe without virulence reversion in accordance with the guidelines of the current licensing authority. However, further studies are needed on the genetic changes and biological characteristics of the mutant virus that occur during successive passages of the attenuated vaccine since the replication and clinical symptoms of the virus increased until the third passage during successive passages of the vaccine virus. Based on this study, it was concluded that virulence reversion and safety evaluation of attenuated vaccines through serial passage in target animals can be useful to evaluate the safety of attenuated viruses.

• BMB Reports
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• v.42 no.8
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• pp.529-534
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• 2009

Marbling score (MS) is the major trait that affects carcass quality in beef cattle. In this study, we investigated the association between genetic polymorphisms of the adipose differentiation-related protein gene (ADFP) and carcass traits in Korean cattle (also known as Hanwoo). Using direct DNA sequencing in 24 unrelated Korean cattle, 25 novel polymorphisms were identified within all exons and their flanking regions of ADFP, including the promoter region (1.5 kb). Among them, 21 polymorphic sites were selected for genotyping in the beef cattle (n = 425). Statistical analyses revealed that one promoter polymorphism (c.-56-18A > G) was associated with MS (P = 0.009). The 'A' allele of c.-56-18A > G exerted a lowering effect on MS, e.g., the lowest MS was found in 'A/A' (MS = 2.09 ${\pm}$ 1.23), intermediate in 'A/G' (MS = 2.11 ${\pm}$ 1.31), and the highest in 'G/G' (MS = 2.47 ${\pm}$ 1.47). Our findings suggest that these polymorphisms in ADFP might be important genetic factors involved in carcass quality in beef cattle.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.746-757
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• 2020

Enterotoxigenic Escherichia coli (ETEC) is the major pathogenic E. coli that causes diarrhea and edema in post-weaning piglets. In this study, we describe the morphology and characteristics of ØCJ19, a bacteriophage that infects ETEC, and performed genetic analysis. Phage ØCJ19 belongs to the family Myoviridae. One-step growth curve showed a latent phase of 5 min and burst size of approximately 20 phage particles/infected cell. Phage infectivity was stable for 2 h between 4℃ and 55℃, and the phage was stable between pH 3 and 11. Genetic analysis revealed that phage ØCJ19 has a total of 49,567 bases and 79 open reading frames (ORFs). The full genomic sequence of phage ØCJ19 showed the most similarity to an Escherichia phage, vB_EcoS_ESCO41. There were no genes encoding lysogeny, toxins, virulence factors, or antibiotic resistance in this phage, suggesting that this phage can be used safely as a biological agent to control ETEC. Comparative genomic analysis in terms of the tail fiber proteins could provide genetic insight into host recognition and the relationship with other coliphages. These results showed the possibility to improve food safety by applying phage ØCJ19 to foods of animal origin contaminated with ETEC and suggests that it could be the basis for establishing a safety management system in the animal husbandry.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.383-390
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• 2014

The safety of a new natural plant composition (ADP) was assessed on the genotoxicity study and 14-day repeat dose toxicity study. ADP contains a mixed water extract obtained from the mixture of Phellodendron cortex (Phellodendron amurense) and Anemarrhena rhizoma (Anemarrhena asphodeloides), and poses the contractile properties mediated by alpha-adrenoceptor of the prostate and urethra as well as antioxidant and anti-inflammatory properties. In order to evaluate genetic safety, in vivo micronucleus test was performed in ICR mice orally administered with three dose levels of 1250, 2500, 5000 mg/kg body weight, and vehicle and positive control. In the 14 days study, Sprague-Dawley rats were treated with ADP at the dose levels of 500, 1000, 2000 mg/kg once a day, and clinical signs, body weights, hematology, serum biochemistry, necropsy findings and organ weights were monitored and examined. In experimental results, ADP treatment, compared with vehicle control, did not induce the micronucleated erythrocytes from mouse bone marrow. In the 14 days study, any significant and toxicological differences in all measurements of parameters were not observed in ADP treatment groups of animals, compared with vehicle treatment. The No-Observed-Adverse-Effect-Level (NOAEL) of ADP in the 14 days study was determined to be greater than 2000 mg/kg/day in both sexes.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.331-338
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• 1999

In the present study, a searching technique for critical slip surface in two dimensional slope stability analysis is proposed. The failure surface generation and analysis has been usually limited to simple geometric shapes. However, more random surfaces need to be examined for some particular ground conditions. For this purpose, random searching technique is developed using genetic algorithm. The generalized limit equilibrium method is employed as the method of stability analysis. Using this technique, the factor of safety is compared with the result by using simplified Bishop's method. In addition, the convergent trend of fitness value is analyzed.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.108-111
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• 2009

DNA-based studies, including cloning and genotyping, have become routine in fungal research laboratories. However, preparation of high-quality DNA from fungal tissue requires much time and labor and is often a limiting step for high-throughput experiments. We have developed a quick and safe (QS) DNA extraction method for fungi. Time efficiency and safety in the QS method were achieved by using plate-grown mycelia as the starting material, by eliminating phenol-chloroform extraction procedures, and by deploying a simple electric grinder. This QS method is applicable not only to a broad range of microbial eukaryotes, including true fungi and oomycetes, but also to lichens and plants.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.1006-1009
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• 2000

In this study, a multi-step optimization technique combined with a simple genetic algorithm is introduced in order to minimize the static compliance, the dynamic compliance, and the weight of a high speed machining center simultaneously. Dimensional thicknesses of the eight structural members on the static force loop are adopted as design variables. The first optimization step is a static design optimization, in which the static compliance and the weight are minimized under some dimensional and safety constraints. The second step is a dynamic design optimization, where the dynamic compliance and the weight are minimized under the same constraints. After optimization, the weight of the moving body only was reduced to 57.75% and the weight of the whole machining center was reduced to 46.2% of the initial design respectively. Both static and dynamic compliances of the optimum design are also in the feasible range even though they were slightly increased than before.