• Transactions of the Korean hydrogen and new energy society
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• v.22 no.5
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• pp.714-720
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• 2011

Ethanol was used as reducing agent to remove $NO_x$ exhaust from the stationary source. Pre-treatment with sulfuric acid over $Ag/Al_2O_3$ catalyst was dedicated to overcome the $SO_2$ poisoning effect. The $NO_x$ reduction experiment was performed under the simulated condition of power plant The increased surface area with higher CPSI devoted to increase de-$NO_x$ yield. De-$NO_x$ yield of the $NO_x$ exhaust containing 20 ppm of $SO_2$ increased after acid treatment with 0.7% $H_2SO_4$ over 4.0% $Ag/Al_2O_3$, where the increased dispersion of Ag found from the results of XRD and XPS was the dominant factor for the increased de-$NO_x$ yield. However, the reason for the decreased de-$NO_x$ yield with the acid treatment of higher concentration (1.0% and 2.0%) of $H_2SO_4$ was found to be due to the formation of $Ag_2SO_4$ crystallites found from XRD result. Acid-treated $Ag/Al_2O_3$ catalyst showed maximum de-$NO_x$ yield at higher temperature than non-treated $Ag/Al_2O_3$ catalyst did.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.432-437
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• 2013

The CO preferential oxidation reaction (PROX) has been done using Cu catalytic active species supported on some of mesoporous silica materials which can facilitate the diffusion of the reactants in order to prevent the poisoning of anode active materials by CO molecules during driving polymer electrolyte fuel cells (PEMFC) in this study. As a result when SBA-15 with large pore used as a support showed excellent CO oxidation activity, especially the activity increased in proportion to the amount of supported Cu. Ti components which was inserted to increase the degree of dispersion of Cu, contributed to improving the performance for CO oxidation at low-temperature. The degree of dispersion of Cu ingredients was the best in the catalyst inserted 20 mol-% Ti into the framework of SBA-15, and CO oxidation activity was also improved.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.28-36
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• 1994

Studies on the food-safety of pheasant and mallard, which belong to wild fowl as new meat resources. were carried out. The results were summarized as follows : 1. Food poisoning bacteria including Salmonella spp, was not detected from the inspections of small intestine, cecum, and rectum. 2. Parasite inspection tests on blood, feces, digestive organ, and thoracic organs were negative. 3. Antibiotic residues from the carcass muscle by simplified disk methods were not detected. 4. Seven different pesticide residue tests, such as DDT and BHT, on the muscle and liver were negative. 5. Four different kinds of toxic heavy metals such as Cd were much lower than the permissible concentration. Studies on the food safety tests and inspections from the pheasant and mallard were revealed that from taking this new food resources, the toxicities would be very low for the human health by the direct influences.

• Journal of Microbiology and Biotechnology
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• v.32 no.10
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• pp.1307-1314
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• 2022

In this study, we sought to investigate the various characteristics of Salmonella spp. isolated from raw chicken meats available in Korean markets. The data collected, such as food source of isolation, sampling information, serotype, virulence, and genetic profile including sequence type, were registered in the database for further comparative analysis of the strains isolated from the traceback investigation samples. To characterize serotype, virulence and gene sequences, we examined 113 domestically distributed chicken meat samples for contamination with Salmonella spp. Phylogenetic analysis was conducted on 24 strains (21.2%) of Salmonella isolated from 113 commercially available chicken meats and by-products, using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Serotyping of the isolated Salmonella spp. revealed S. Enteritidis in 11 strains (45.8%), S. Virchow in 6 strains (25%), S. Montevideo in 2 strains (8.3%), S. Bsilla in 2 strains (8.3%), S. Bareilly in 1 strain (4.2%), S. Dessau in 1 strain (4.2%), and S. Albany in 1 strain (4.2%). The genetic correlation indicated that 24 isolated strains were classified into 18 clusters with a genetic similarity of 64.4-100% between them. Eleven isolated S. Enteritidis strains were classified into 9 genotypes with a sequence identity of 74.4%, whereas the most distantly related S. Virchow was divided into five genotypes with 85.9% identity. Here, the MLST analysis indicated that the major Sequence Type (ST) of the Salmonella spp. isolated from domestic chicken sold in Chungcheong Province belongs to the ST 11 and 16, which differs from the genotype of Salmonella isolated from imported chicken. The differential sequence characteristics can be a genetic marker for identifying causative bacteria for epidemiological investigations of food poisoning.

• International Journal of Advanced Culture Technology
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• v.10 no.2
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• pp.12-20
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• 2022

In order to prevent mass infection of food poisoning in children, children's foodservice facilities should always thoroughly manage the hygiene and safety of meals. In this study, the hygiene management levels of daycare centers and kindergartens were compared according to the characteristics of foodservice facilities for four years from 2018, and the effect of the number of visits on the meal hygiene management scores analyzed. The facilities were divided into a small-scale and the group foodservice facilities and was divided into the Sprout group and the Fruit group according to the meal hygiene management level. As a result, the meal hygiene management of the Fruit group was generally better than that of the Sprout group, and the meal hygiene management scores in the second half of each year increased compared to the first half of the year. In addition, it was confirmed that the meal hygiene management scores in 2020, when the number of visits to foodservice facilities decreased due to COVID-19, was the worst compared to other years, and the decrease in the number of visits could affect the level of hygiene management. In conclusion, meal hygiene management of children's foodservice facilities should be applied differently depending on the characteristics of the facilities. Moreover, the number of visits and the hygiene management scores correlated, so it is considered that the appropriate number of visits should be maintained to improve the meal hygiene management level. However, in situations where it is necessary to prevent the spread of mass infectious diseases such as COVID-19, other active measures to replace visits should be proposed.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.26.1-26.15
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• 2023

Background: The objective of this study is to investigate the differences in incidence rates of targeted diseases by classification of occupations among construction workers in Korea. Methods: In a subject-based cohort of the Korean Construction Worker's Cohort, we surveyed a total of 1,027 construction workers. As occupational exposure, the classification of occupations was developed using two axes: construction business and job type. To analyze disease incidence, we linked survey data with National Health Insurance Service data. Eleven target disease categories with high prevalence or estimated work-relatedness among construction workers were evaluated in our study. The average incidence rates were calculated as cases per 1,000 person-years (PY). Results: Injury, poisoning, and certain other consequences of external causes had the highest incidence rate of 344.08 per 1,000 PY, followed by disease of the musculoskeletal system and connective tissue for 208.64 and diseases of the skin and subcutaneous tissue for 197.87 in our cohort. We especially found that chronic obstructive pulmonary disease was more common in construction painters, civil engineering welders, and civil engineering frame mold carpenters, asthma in construction painters, landscape, and construction water proofers, interstitial lung diseases in construction water proofers. Conclusions: This is the first study to systematically classify complex construction occupations in order to analyze occupational diseases in Korean construction workers. There were differences in disease incidences among construction workers based on the classification of occupations. It is necessary to develop customized occupational safety and health policies for high-risk occupations for each disease in the construction industry.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.77-92
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• 2014

Fermented foods have often been implicated as causative agents in poisoning due to toxic levels of biogenic amines. Cheese, a milk-based fermented food, is the product most likely to contain potentially harmful levels of biogenic amines, such as tyramine, histamine, putrescine, and so on. Recently, the risk awareness of a dietary uptake of high loads of biogenic amines has increased. Hence, we here review the published literature on several factors known to affect the biosynthesis of biogenic amines and their accumulation in milk-based foods. Furthermore, with regard to risk analysis, we discuss the control of factors related to the synthesis and accumulation of biogenic amines as a means to reduce their incidence in milk-based products, and thus to increase food safety.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.545-557
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• 2017

Objective: The aim of this study was to find risk factors in cultivating ginseng based on risk assessments and suggest safety measures for main risks. Background: Safety education and training is one of the practical and effective methods to prevent occupational accidents and injuries. In agricultural sector, there are few contents of safety education as compared to other industries. Especially, farm work has different cultivation characteristics according to the crops, so it needs special education materials for each crop. Among the various types of crops, ginseng contains various risk factors due to its long cultivating period and unique environment. Therefore, safety education material specified for ginseng is necessary to improve ginseng farmers' safety. Method: Risk assessment for cultivating tasks of ginseng was carried out through data obtained from various methods (site survey, interview, literature survey). To improve objectivity, the risk assessment was applied with 3-criteria (researcher estimate, interview, previous research results). Finally, the three high-risk tasks were selected and safety measures for those tasks were provided. Results: Three tasks, such as 'Mounting, maintenance and removing supports', 'Pest control' and 'Harvest', were selected as risky tasks among total tasks. (1) In 'Mounting' and maintenance and removing supports', the farmers found to be exposed to the risks of musculoskeletal disorders and accidents related to operating the tablet machine. (2) In 'Pest control', agrichemical poisoning, musculoskeletal disorders and hyperthermia were main risks. Finally, (3) In 'Harvest', the farmers are mainly exposed to the possibility of accidents of agricultural machines and risks of musculoskeletal disorders. Thus, it needs to apply appropriate safety measures to those risky tasks, such as safety guidelines, convenience equipment, protective kit, and so on. Conclusion: This study can be used as basic data for agricultural safety and expected that it would be useful for further study. In addition, the results of the research will be produced in the form of animation, which will enhance the safety consciousness for aged farmers. Application: The result of this study can be used in developing safety education materials for ginseng farmers which is essential to prevent occupational accidents and injuries among ginseng farmers.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.47-53
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• 2007

The DY1 strain of Gram-positive, rod-shaped bacteria was isolated from the soil sample collected from Daeam mountain, Korea. The culture filtrate of DY1 strain showed a broad spectrum of antimicrobial activity on various pathogenic and food poisoning enteric bacterial species tested in vitro. It showed significant growth-inhibitory effect on Salmonella enterica sp., Shigella sp., pathogenic Escherichia coli, Vibrio cholerae, Vibrio parahemolyticus, and Yersinia enterocolitica. For the identification of the DY1 strain, morphological, biochemical and molecular phylogenetic approaches were performed. The DY1 strain was found to be a member of the genus Paenibacillus on the basis of morphological and biochemical analyses. The 16S rDNA of DY1 showed the highest pairwise identity with Paenibacillus polymyxa with 99.79% (1,413 bp/1,416 bp). The antimicrobial entity from DY1 looked different from preciously reported ones and seems to have a great potential to be further studied as a candidate of new antibiotics to control multi-drug resistant pathogens.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.509-514
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• 2011

This study was conducted to investigate the phenotypic and genotypic characteristics of Korean isolates of Cronobacter spp. (Enterobacter sakazakii). A total of 43 Cronobacter spp., including 5 clinical isolates, 34 food isolates, 2 environmental isolates, and 2 reference strains (C. sakazakii ATCC 29004 and C. muytjensii ATCC51329) were used in this study. Korean isolates of Cronobacter spp. were divided into 11 biogroups according to their biochemical profiles and 3 genomic groups based on the analysis of their 16S rRNA gene sequences. Biogroups 1 and 2 contained the majority of isolates (n=26), most of which were contained in 16S rRNA cluster 1 (n=34). Korean isolates of Cronobacter spp. showed diverse biochemical profiles. Biogroup 1 contained C. sakazakii GIHE (Gyeonggido Research Institute of Health and Environment) 1 and 2, which were isolated from babies that exhibited symptoms of Cronobacter spp. infection such as gastroenteritis, sepsis, and meningitis. Our finding revealed that Biogroup 1, C. sakazakii, is more prevalent and may be a more pathogenic biogroup than other biogroups, but the pathogenic biogroup was not represented clearly among the 11 biogroups tested in this study. Thus, all biogroups of Cronobacter spp. were recognized as pathogenic bacteria, and the absence of Cronobacter spp. in infant foods should be constantly regulated to prevent food poisoning and infection caused by Cronobacter spp.