• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.500-505
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• 2019

Staphylococcus aureus is a round-shaped, gram-positive bacterium that can cause numerous infectious diseases ranging from mild infections such as skin infections and food poisoning to life-threatening infections such as sepsis, endocarditis and toxic shock syndrome. Various antibiotic-resistant strains of S. aureus have frequently emerged, threatening human lives significantly. Despite much research on the genetics of S. aureus, many of its genes remain unknown functionally and structurally. To counteract its toxins and to prevent the antibiotic resistance of S. aureus, our understanding of S. aureus should be increased at the proteomic scale. SAV0927 was first sequenced in an antibiotic resistant S. aureus strain. The gene is a conserved hypothetical protein, and its homologues appear to be restricted to Firmicutes. In this study, we determined the crystal structure of SAV0927 at $2.5{\AA}$ resolution. The protein was primarily dimeric both in solution and in the crystals. The asymmetric unit contained five dimers that are stacked linearly with ${\sim}80^{\circ}$ rotation by each dimer, and these interactions further continued in the crystal packing, resulting in a long linear polymer. The crystal structures, together with the network analysis, provide functional implications for the SAV0927-mediated protein network.

• The Korean Journal of Food And Nutrition
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• v.33 no.6
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• pp.702-709
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• 2020

The purpose of this study was to evaluate microbiological contamination of knives and cutting boards in child-care centers. Materials used in this study were swabbed of cutting boards and knives (blade, handle of knife, and joint of handle and blade) in 129 child-care centers. Mean values of total aerobic bacteria of swabs of knives and cutting boards were 1.7±0.7 log cfu/100 ㎠ and 1.7±0.9 log cfu/100 ㎠, respectively. Contamination levels of coliform bacteria from knives and cutting boards were 1.5±0.6 log cfu/100 ㎠ and 1.7±0.8 log cfu/100 ㎠, respectively. Comparing microbiological contamination levels of knives and cutting boards according to type and size of child-care centers, there was no significant difference. Bacillus cereus was detected in knife handles and cutting boards. Diarrhea-type toxin gene (entFM) was detected in B. cereus isolates. Antibiotic resistance tests showed that B. cereus was resistant to β-lactam antibiotics. To reduce microbiological contamination levels of knives and cutting boards in child-care centers and prevent food poisoning from bacteria contamination, continuous education by children's food-service management center is needed for sterilization and disinfection of knives and cutting boards.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.132-136
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• 2007

Disinfectants/sanitizers, showing the bactericidal activity of $5log_{10}$ reduction against E. coli ATCC 10536 and Staphylococcus aureus ATCC 6538 used far assessing disinfectants/sanitizers efficacies, were examined whether showing similar efficacies against Salmonella spp. and Listeria monocytogenes, the major food poisoning bacteria, isolated from foods in current Korean market. The bactericidal efficacies on sodium hypochlorite and benzalkonium chloride were assessed by quantitative suspension tests in both 'clean' and 'dirty' conditions, respectively. Test organisms were consisted of E. coli ATCC 10536, Staphylococcus aureus ATCC 6538, Salmonella typhimurium ATCC 13311, Salmonella Enteritidis ATCC 13076, Listeria monocytogenes ATCC 19111, 10 kinds of Salmonella spp. from foods, and 11 kinds of Listeria monocytogenes from foods. More than $5log_{10}$ reduction in viable count for all strains was only achieved with benzalkonium chloride at the tolerance exemption concentration under dirty conditions. However, all strains were achieved more than $5log_{10}$ reduction under clean conditions.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.104-111
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• 1993

Trace elements are important components in the biological system, as a structural material and metabolic controller. Neutron activation analysis (NAA) with high neutron flux and high energy resolution Ge (Li) detector coupled to multichannel analyzer (MCA) has been one of the most accurate method for the determination of ultra-trace level components, and is applicable to biological material. In human body, the NAA can be used for quantitation of trace elements in various organs and tissue with endocrinological and metabolic disease and industrial metal poisoning. In this study, Triga Mark III nuclear reactor in Korea Atomic Research Institute was used for quantitation of trace eleement in human lung cancer tissues by neutron activation analysis. In the squamous cell carcinoma tissues, Br, Hg, La, Sb, Sc, Cl, Fe and I content were lower than normal lung tissues, and K, Rb and Se content were higher. In the adenocarcinoma tissues, Fe, Au, La, Sc and Zn content were lower than normal lung tissues, and Rb, Co and Se content were higher. Rb content was higher in the adenocarcinoma tissues than in the squamous cell carcinoma tissues. Fe and Na content were higher in the squamous cell carcinoma tissues than in the adenocarcinoma tissues.

• The Korean Journal of Emergency Medical Services
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• v.12 no.1
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• pp.69-80
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• 2008

During New year's day and Thanksgiving holiday, the 1339 Information Center in Gwangju and Jeonnam received an emergency medical situation and carried out the analysis as follows ; 1. The reason for the higher phone guidance(72%) of the hospital was based on the simple query for the pain control rather than emergency care. This was explained by the unfamiliar environment of the holiday movers. Pharmaceutical guidance(12.6%) in rural area was also given during the holidays. 2. The disease counselling(2.4%) and emergency treatment instruction(First Aid)(1.6%) decreased because of the small number of request for the diseases. This explained the decrease of the disease counselling. 3. The phone calls increased 8-13 times more than usual. Five-day holidays could have more emergency patients than three-day holidays. During New year's day and Thanksgiving day, the number of received phone calls was 6,444(25.7%) and this accounted for one fourth of the total number in 2007. 4. The number of the patients increased on New year's day and Thanksgiving day because most of the medical institutions and pharmacy were off duty. 5. The patients were centered in Internal medicine and pediatrics. This showed the food-borne diseases and air-borne infection such as common cold. 6. During Thanksgiving day, ophthalmologic patients having viral keratoconjunctivitis(Apollo eye disease) increased 8 folds than in New year's day. It was estimated from the continuous epidemic of Apollo eye disease. 7. There broke out the traffic accidents, food poisoning, infectious diseases, dermatological diseases due to seasonal and environmental changes during the holiday move.

• Journal of Power System Engineering
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• v.22 no.6
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• pp.51-57
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• 2018

In Korea, the Air Quality Conservation Act and the Petroleum and Petroleum Substitute Fuel Business Act stipulate certain quality standards for fuels distributed in Korea, thereby striving to reduce vehicle performance and emissions. Domestic petroleum products import and produce all the crude oil from each oil refiner so that the quality of the petroleum product is different according to the characteristics of the crude oil. As a result, vehicles have been improved by using the physical properties calculated through the physical property measurement that has tried to improve the accuracy of the measurement of the energy consumption efficiency of the automobile by using standard fuel from abroad. In this study, the same test procedure and method as the test method of domestic gasoline vehicle emission are applied using four samples of gasoline and the latest gasoline vehicle which are actually distributed, and the performance evaluation is performed. The purpose of this study is to contribute to improvement of vehicle technology and fuel quality by collecting necessary basic data and obtaining data on the effect of differences in gasoline property on vehicle emissions. The results of the test showed that the emission of gases (NMOG, CO) from gasoline vehicles was the most influenced by the sulfur content, unlike the previous studies that the vehicles emission had the greatest influence on the distillation characteristics and the specific gravity of aromatic compounds. The catalytic reaction such as the poisoning action of the three-way catalyst which is the abatement device was interfered and the emission was increased. The distillation characteristics and specific gravity of aromatic compounds were found to affect the emission of vehicles. According to the physical properties of the fuel, the emission difference was 28.0% in the urban mode and 17.6 % in the highway mode.

• Journal of Hydrogen and New Energy
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• v.26 no.1
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• pp.21-27
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• 2015

Hydrogen production from commercial diesel fuels is an attactive option for energy generation purpose due to the low cost and good availability of diesel fuels. However, in order to utilize commercial diesel fuels, the sulfur contents must be removed down to approximately 0.1 ppm level to protect the fuel cell catalysts from poisoning. Commercial catalysts $CoMo/Al_2O_3$ and $NiMo/Al_2O_3$ were tested for HDS (Hydrodesulfurization) of model diesel and commercial diesel. The experimental conditions were $250-400^{\circ}C$ and LHSV (Liquid Hourly Space Velocity) $0.27-2.12hr^{-1}$. $NiMo/Al_2O_3$ was found to be more effective than $CoMo/Al_2O_3$ in removing sulfur from model diesel. Based on the experimental results of model diesel, commercial diesel fuel purchased from a local petrol station was tested for HDS using $NiMo/Al_2O_3$. The GC-SCD (Gas Chromatography Sulfur Chemiluminescence Detector) results showed that the DMDBT (Dimethyldibenzothiophene) derivatives were fully removed from the commercial diesel fuel proving that HDS with $NiMo/Al_2O_3$ is technically feasible for industrial applications.

• Journal of The Korean Society of Clinical Toxicology
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• v.16 no.1
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• pp.25-32
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• 2018

Purpose: Methamphetamine is an ongoing illegal drug problem worldwide, and its use in South Korea has spread over the last few years. In this study, a clinical review of patients who visited emergency medical centers with positive methamphetamine tests was conducted. Methods: Patients underwent methamphetamine screening based on physician suspicion over a period of 13 years. Their patient characteristics, clinical features, and drug administration properties were described. Results: A total of 297 patients were included, with 19 positive methamphetamine results. Patient age ranged from 21 to 84, with a mean of 37.52. Additionally, 13 were male and 6 were female. The mean BP, PR, RR were 131/82 mmHg, 94/min, 20/min. Saturation levels were all over 95%. Five patients had a psychiatric history. Patient showed varied symptoms ranging from mental changes to chest discomfort. In addition, seven showed abnormal electrocardiography findings and one showed elevated cardiac enzyme levels. Other laboratory results revealed no significantly abnormal results. Six patients also suffered from related trauma. The majority of patients consumed the methamphetamine orally, with unknown motivation at unknown locations. Most were transported by 119 and six patients co-ingested other drugs. Conclusion: Patients who showed positive results to a methamphetamine screening test in Korea visited the emergency medical center mostly by 119 and were unaware of or reluctant to reveal the fact that they had ingested methamphetamine. Emergency physicians should be more aware of the possibility that a patient may have consumed methamphetamine.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.838-843
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• 2005

Bacterial suspension test was used to establish Standardization Test Method to investigate bactericidal activity of disinfectant/sanitizer product. Using acceptable verification methodology, test substance showing 5 log or higher reduction in viable count against Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538, representing Gram-negative and -positive bacteria, respectively, under test conditions for $5\;min{\pm}10\;sec\;at\;20{\pm}1^{\circ}C$ was considered to have sanitizing capability. All disinfectant/sanitizer products tested under manufacturer's recommended in-use condition gave good reduction values against major food-poisoning bacteria. This standardized method was valuable for evaluating efficacy of disinfectants/sanitizers and could be used as Standardization Test Method for assessing bactericidal activity

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.6
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• pp.545-554
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• 2014

In general, odorant was added to fuel gases, such as LPG, LNG and city gas, to prevent gas poisoning, ignition, explosion, or other accident caused by fuel gases, and to enable immediate and easy detection of fuel-gas leakage by emitting an offensive smell. This study describes a study on the exhaust emissions characteristics and fuel economy of liquefied petroleum gas (LPG) vehicle using LPG fuel with new sulfur free odorant. New sulfur free odorant was added to LPG to reduce sulfur content of the LPG. Its performance and exhaust emission were compared to those of LPG with sulfur containing odorant (EM, ethyl mercaptan). Engine performance using LPG with sulfur free odorant was similar to that with sulfur-containing odorant. Exhaust emissions from the LPG vehicle with LPG including sulfur free odorant were also similar to those with LPG including sulfur containing odorant in the FTP 75 and NEDC mode. There experimental results suggest that the sulfur free odorant may substitute for the sulfur containing odorant in LPG fuel.