• Applied Chemistry for Engineering
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• v.26 no.4
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• pp.400-405
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• 2015

Traditional anti-reflective (AR) coating films prepared using tetraethylorthosilicate (TEOS) as a precursor absorbs water easily in addition to having a weak abrasion resistance. To improve the transmittance, hydrophobicity and abrasion resistance of AR coating film, various AR coating films were prepared using methyltrimethoxysilane (MTMS) as a precursor in addition to introducing a fluoroalkylsilane, acid catalyst, base catalyst and acid-base two step catalyst. The prepared AR coating films were then characterized by UV-Vis spectroscopy, contact angle analyzer, atomic force microscope (AFM), pencil scratch hardness test and cross-cut test. As a result, the transmittance of bare glass was 90.5%, while that of AR coating glass increased to 94.8% at curing temperature of $300^{\circ}C$. When the fluoroalkylsilane was added, the water contact angle of AR coating film increased from $96.3^{\circ}$ to $108^{\circ}$, indicating that the hydrophobicity of the film was greatly improved. The abrasion resistance of AR coating film was also improved by the acid catalyst, whereas the transmittance increased by the base catalyst. In the case of AR coating film prepared using an acid-base two step catalyzed reaction, both the transmittance and abrasion resistance of the film was synergistically enhanced as compared with those of AR coating films prepared without introduction of a catalyst.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.254-259
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• 2016

Acinetobacter sp. B-W producing siderophore, 2, 3-dihydroxybenzoic acid (DHB) was analyzed for plasmid content. Strain B-W harbored plasmid of 20 kb in size. Growth at $43^{\circ}C$ was effective in producing mutant cured of plasmid of strain B-W. This mutant lost the ability to produce 2, 3-DHB. Formation of siderophore halos on the chrome azurol S (CAS) agar medium was not detected by cured strain B-W. pHs of supernatants of wild type strain B-W and cured mutant grown in glucose and $MnSO_4$ containing medium at $28^{\circ}C$ for 3 days were 4.5 and 8.5, respectively. Antibiotic resistance against ampicillin, actinomycin D, bacitracin, lincomycin, and vancomycin was lost in cured mutant. Plasmid curing of strain B-W resulted in drastic reduction of minimal inhibitory concentration (MIC) of several antibiotics. E. coli $DH5{\alpha}$ was transformed with plasmid isolated from strain B-W. The transformant E. coli $DH5{\alpha}$ harbored a plasmid of the same molecular size as that of the donor plasmid. Transformant E. coli $DH5{\alpha}$ produced 2, 3-DHB and contained antibiotic resistant ability. Thus a single plasmid of 20 kb seemed to be involved in 2, 3-DHB production. Genes encoding resistance to antibiotics were also supposed to be located on this plasmid.

• Journal of Environmental Health Sciences
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• v.39 no.3
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• pp.239-246
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• 2013

Objectives: Antimicrobial resistance and multidrug resistance patterns have been studied with a total of 189 samples of Salmonella Enteritidis and Salmonella Typhimurium isolated from diarrhea patients in Incheon from 2008 to 2012. Methods: Antimicrobial resistance tests were determined by Disc Diffusion method. Results: The serological distribution of Salmonella spp. showed 108 strains (30.1%) of S. Enteritidis, 81 strains (22.6%) of S. Typhimirium, eight strains (8.0%) of S. Typhi, 11 strains ( 3.1% ) of S. Paratyphi, and the 151 other strains (42.1%). The separation rate of Salmonella spp. by year showed 14.5% (52 strains) in 2008, 13.6% (49 strains) in 2009, 22.8% (82 strains) in 2010, 25.3% (91 strains) in 2011, and 23.7% (85 strains) in 2012. Additionally, the separation rate of S. Enteritidis and S. Typhimirium in 2010 was the highest. The Salmonella spp. isolated from diarrhea patients showed significant differences according to age (p<0.05), gender (p<0.01) and medical institution (p<0.05). The highest resistance was found to the following antimicrobial agents: imipenem 77 strains, ampicillin 47 strains, ciprofloxacin 34 strains, nalidixic acid 29 strains for S. Enteritidis, and ampicillin 45 strains, nalidixic acid 45 strains for S. Typhimurium. Separated S. Enteritidis and S. Typhimurium resistance to the antibiotics by the year showed significant differences (p<0.05). The patterns of multidrug resistance rates were 43.1% (47 strains) for one drug, 8.3% (9 strains) for two drugs, 11.0% (12 strains) for three drugs, 15.62% (17 strains) for four drugs, and 13.7% (15 strains) for five or more drugs for S. Enteritidis. For S. Tyhpimurium, the rates were 15.0% (12 strains) for one drug, 10.0% (8 strains) for two drugs, 6.3% (five strains) for three drugs, 18.7% (15 strains) for four drugs, and 23.8% (19 strains) for five or more drugs. Conclusion: The antibiotic resistance issue is directly related to people's lives. Thus, the usage of antibiotics should be reduced in order to manage antibiotic resistance.

• Journal of Animal Science and Technology
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• v.58 no.3
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• pp.10.1-10.10
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• 2016

Background: Airag, alcoholic sour-tasting beverage, has been traditionally prepared by Mongolian nomads who naturally ferment fresh mares' milk. Biochemical and microbiological compositions of airag samples collected in Ulaanbaatar, Mongolia and physiological characteristics of isolated lactic acid bacteria were investigated. Methods: Protein composition and biochemical composition were determined using sodium dodecyl sulfate-gel electrophoresis and high performance liquid chromatography, respectively. Lactic acid bacteria were identified based on nucleotide sequence of 16S rRNA gene. Carbohydrate fermentation, acid survival, bile resistance and acid production in skim milk culture were determined. Results: Equine whey proteins were present in airag samples more than caseins. The airag samples contained 0.10-3.36 % lactose, 1.44-2.33 % ethyl alcohol, 1.08-1.62 % lactic acid and 0.12-0.22 % acetic acid. Lactobacillus (L.) helveticus were major lactic acid bacteria consisting of 9 isolates among total 18 isolates of lactic acid bacteria. L. helveticus survived strongly in PBS, pH 3.0 but did not grow in MRS broth containing 0.1 % oxgall. A couple of L. helveticus isolates lowered pH of skim milk culture to less than 4.0 and produced acid up to more than 1.0 %. Conclusion: Highly variable biochemical compositions of the airag samples indicated inconsistent quality due to natural fermentation. Airag with low lactose content should be favorable for nutrition, considering that mares' milk with high lactose content has strong laxative effect. The isolates of L. helveticus which produced acid actively in skim milk culture might have a major role in production of airag.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.430-438
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• 1996

The eleven strains, which could be used lactic and acetic acids as carbon sources, were isolated from kimchi and identified; the strains were facultative microorganisms which could be grown at low temperature (10$\circ$C) and around pH 3.2. As results of morphological, biochemical and physiological tests, 5 species of 3 genera were identified as Debaryomyces coudertii, Pichia edia, Pichia chambardii, Pichia haplophilia and Saccharomyces fermentati. Each strain was grown in basal media. In acidic resistance and acid utilization test, Saccharomyces sp. YK- 17 and Saccharomyces fermentati YK-19 were grown well in basal and YM media containing 0.3% lactic acid. And two strains were grown in basal and YM media containing O.3% lactic acid and 0.6% acetic acid. Since strain YK-19 was grown better at 10$\circ$C than that in 25$\circ$C, strain YK-19 was known to be a psychrophilic strain.

• Textile Coloration and Finishing
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• v.35 no.4
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• pp.221-230
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• 2023

Meta-aramid and polyamic acid were separated and the manufactured films were analyzed for their integration and logarithmic properties. The miscibility of meta-aramid and polyamic acid was analyzed by Fourier transform infrared spectroscopy and scanning electron microscopy. Using calorimetric analysis and differential scanning calorimetry, the storage of meta-aramid and polyamic acid, indicated on the right side of the column, was analyzed. It was confirmed that the initial thermal resistance occurs because the polyamic acid is accounted for in the meta-aramid, and the glass transition temperature and persistence phenomenon are explained.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.76.2-77
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• 2003

The complete nucleotide sequences of genomic RNA of an isolate of soybean mosaic virus (SMV-CN18), which has ability to overcome Rsv resistance of soybean, have been determined. A large open reading frame encodes a polyprotein of 3068 amino acids with a predicted Mr of 350 kDa. Based on comparison with the proposed cleavage site of other potyviral polyproteins, nine mature proteins are predicted as a following order, P1, HC-Pro, P3, CI, 6K, VPg, NIa, NIb and coat protein (CP). The mature proteins of the strain share various amino acid identity with known SMV-G2, -G7 and -N strain, with the greatest variability occurring in the P1 (91 ％, 88 ％, 96％)and the lowest variability in the CP (100 ％, 99 ％, 100 ％). In addition, 5' untranslated region determined by 5' RACE is much more various than any coding regions. Difference in amino acid sequences throughout the genome is discussed in relation to resistance and susceptibility of soybean cultivars to SMV-CNl8.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.286-295
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• 2011

Bacteria resistant to various antibiotics have recently become an issue of the utmost importance. Resistant strains are not uncommon, even in municipal drinking water sources. The health threat posed by resistant, pathogenic bacteria has serious ramifications for both public health and agriculture. In this study, we isolated antibiotic resistant bacteria from water samples from the Han River, Korea, which is contaminated by the wastewater from many industrial complexes, hospitals, agricultural and animal husbandry estates, and from wastewater treatment facilities. We determined the degrees of resistance to various antibiotics exhibited by the isolated strains. The similarities between the isolated $E.$ $coli$ strains were examined, using the pulsed field gel electrophoresis and multilocus sequence typing, in order to trace their origins and to explore the syntechnic adaptations and pathogenicity of the various strains and relate these to their genetic sequence. A total of 25 $E.$ $coli$ strains were isolated from six stations along the Han River. All the 25 strains exhibited resistance to ampicillin. We also investigated resistance to amoxicillin, clavulanic acid, cefazolin, cofoxitin, cefotaxime, cefpodoxime, ceftriaxone, cefepime, nalidixic acid, aztreonam, ciprofloxacin, streptomycin, gentamicin, chloramphenicol and imipenem. Based on the ESBL detection, 14 strains belonged to the ESBL producing strains. The number of the clonal complex producing strains was 5 among the 14 isolated strains. The 5 strains were included in the 168, 23, 38, 469, 156 clonal complex, respectively. The rest 9 strains were not included in the clonal complex, but showed independent STs.

• The Korean Journal of Ecology
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• v.7 no.3
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• pp.99-108
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• 1983

Diurnal acid fluctuation, stomatal resistance, and solar radiation with regard to the cladode orientation were investigated in Opuntia lanceolata Haw. growing at WPeolryeong-ri, Hallim-eup, Chejudo, Korea. Diurnal changes of titratable acidity showed the typical CAM pattern in all investigated cladodes. Water tissue in the cladode had the same pattern of acid fluctuation as mesophyll tissue. Stomatal resistance was low during the night, increased rapidly to be a peak right after sunrise and decreased again thereafter. The southern side of the cladode showed higher stomatal resistance than the northern side during the day time. It suggests that the stomata of the northern side opens under diffuse radiation. The amount of solar radiation varied depending upon the cladode orientation. It is thought that C4 acids move inter and intra mesophyll tissues in the cladode through the unknown pathways. RuBP carboxyulase activity in the cladode was very high at 14:00, but was not significant at 01:00. PEP-carboxylase had high activities both at 14:00 and at 01:00. The results of this study showed the possibility that O. lanceolata Haw. had the C3, C4 and CAM photosynthetic patterns under the environmental conditions at Weolryeong-ri.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3657-3661
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• 2012

HBV infection is contagious and may be transmitted vertically or horizontally by blood products and body secretions. Over 50% of Iranian carriers have contracted the infection prenatally, making this the most likely route of transmission of HBV in Iran. This study assesses the resistance to Lamivudine in patients with chronic hepatitis B infection using a new ZNA probe Real Time PCR method. To evaluate the effectiveness of Lamivudine therapy for chronic hepatitis B infection, a study was conducted on 70 patients (63 men and 7women), who had received the drug first line. All patients were tested for the presence of HBsAg and HBeAg, the serum ALT level and the HBV DNA load before and after treatment. In all samples resistance to Lamivudine was tested with the ZNA Probe. Our results showed that ZNA Probe Real Time PCR method could detect wild type,YMDD, and its mutants, tyrosine-isoleucine-aspartate-aspartate and tyrosine-valine-aspartate-Aspartate. Among an estimated seventy patients with chronic hepatitis B infection, 18 (25.7%) were resistant to lamivudine. Only one patient was negative for presence of HBS-Ag (5.6%) and two patients were negative for HBe-Ag (11.1%). Real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for mutations in the YMDD motif, which will be essential for monitoring patients undergoing Lamivudine antiviral therapy.