• The Journal of Engineering Geology
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• 제22권1호
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• pp.67-81
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• 2012

The physical, chemical, and biological properties of clogging materials formed within groundwater wells in the Mt. Geumjeong area, Busan, Korea, were characterized. The particle size distribution (PSD) of clogging materials was measured by a laser analyzer. XRD, SEM, and TEM analyses were performed to obtain mineralogical information on the clogging materials, with an emphasis on identifying and characterizing the mineral species. In most cases, PSD data exhibited an near log-normal distribution; however, variations in frequency distribution were found in some intervals (bi-or trimodal distributions), raising the possibility that particles originated from several sources or were formed at different times. XRD data revealed that the clogging materials were mainly amorphous ironhydroxides such as goethite, ferrihydrite, and lapidocrocite, with lesser amounts of Fe, Mn, and Zn metals and silicates such as quartz, feldspar, micas, and smectite. Reddish brown material was amorphous hydrous ferriciron (HFO), and dark red and dark black materials were Fe, Mn-hydroxides. Greyish white and pale brown materials consisted of silicates. SEM observations indicated that the clogging materials were mainly HFO associated with iron bacteria such as Gallionella and Leptothrix, with small amounts of rock fragments. In TEM analysis, disseminated iron particles were commonly observed in the cell and sheath of iron bacteria, indicating that iron was precipitated in close association with the metabolism of bacterial activity. Rock-forming minerals such as quartz, feldspar, and micas were primarily derived from soils or granite aquifers, which are widely distributed in the study area. The results indicate the importance of elucidating the formation mechanisms of clogging materials to ensure sustainable well capacity.

• Journal of Food Hygiene and Safety
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• 제31권6호
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• pp.458-464
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• 2016

Mulberry is considered a healthy food for antioxidants and many other beneficial nutrients. However, food safety concerns exist as this commodity scarcely passes through a sanitizing step due to the fragile nature of mulberry fruits. Fermented mulberry wort is one traditional way to utilize and preserve mulberries by mixing with sugars although hygienic practices are not often implemented. The purpose of this study was to investigate the fate of foodborne pathogens in fermented mulberry wort. Microbial population of inoculated E. coli in mulberry wort showed a decreasing pattern as the fermentation progressed. A quicker decrease was observed in the mulberry wort mixed with sugar at 1 to 0.8 ratio (w/w, mulberry: sugar) compared to 1 to 1 ratio, which could be due to the amount of acids generated during the fermentation process. When fully-fermented mulberry wort was contaminated with foodborne pathogens, they all decreased in population although their deceasing patterns varied depending on the species of tested bacteria. Steep deceases in population of inoculated foodborne pathogens were observed when the fermented wort was stored at $30^{\circ}C$ in comparisons to the other storage temperature, 5 and $20^{\circ}C$, regardless of bacterial species. This study necessitates the optimization of a sanitizing process during fermentation and storage of mulberry wort.

• Korean Journal of Food Science and Technology
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• 제50권5호
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• pp.535-542
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• 2018

The current study investigated the beneficial effects of 15 essential oils isolated from tree branches, leaves, and flowers. Among these oils, clove bud and Illicium anisatum oils showed the most potent anti-oxidant effects on 1,1-diphenyl-2-picrylhydrazyl and 2,2'azinbis-(3-ethyl-benzothiazoline-6-sulfonic acid) radical scavenging activities. Next, we evaluated the antibacterial effects of 15 essential oils on Staphylococcus aureus, Listeria monocytogenes, Escherichia coli O157:H7, Salmonella typhimurium, and Streptococcus mutans. Clove bud significantly decreased growth of 5 bacterial strains. In addition, clove bud, Magnolia kobus, Picea abies and Chamaecyparis obtuse significantly reduced growth of the fungi, Aspergillus fumigatus, Aspergillus ochraceus, Candida albicans and Trichophyton rubrum. Additionally, clove bud also remarkably reduced the expression of cyclooxygenase-2 and inducible NO synthase in lipopolysaccharide-activated RAW264.7 cells. These results indicate that essential oils isolated from trees, which exhibit antioxidant, antibacterial, antifungal and anti-inflammatory properties, may be potentially useful in the development of cosmetic ingredients.

• Tuberculosis and Respiratory Diseases
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• 제47권2호
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• pp.209-217
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• 1999

Backgrounds: To investigate the role of CT as a screening tool and to compare the diagnostic accuracy with that of the fiberoptic bronchoscopy (FOB) in evaluating the causes of hemoptysis. Methods: The retrospective review of plain chest radiograph, CT and FOB was done in 72 patients with hemoptysis. The diagnosis were confirmed by histology (n=33), bacterial culture (n=6), cytology (n=3), serology (n=2), skin test (n= 1), clinical response (n=5), and airway disease mainly by HRCT (n=22). Results: The causes of hemoptysis were shown to be lung cancer (n=29), bronchiectasis (n=19), tuberculosis (n=12), aspergilloma (n=5), invasive aspergillosis (n=l), COPD (n=3) and others (n=3). The sensitivity was 100% and 91,7% by CT and FOB respectively. The diagnostic compatibility was 95.8% and 59.7% by CT and FOB respectively. The diagnostic compatibility in cases with central airway disease was 96.3% and 100 % in CT and FOB. In parenchymal disease, CT and FOB showed 91.3 % and 43.5 % of compatibility, respectively. airway disease, CT and FOB showed 100% and 31.8% compatibility, respectively. That is to say, CT has higher sensitivity and diagnostic compatibility than FOB for identifying the causes of hemoptysis, and is more helpful for patients with hemoptysis from parenchymal or airway disease. FOB had the advantage in obtaining histologic, cytologic and bacteriologic diagnosis with biopsy or washing Conclusion: CT should be used as the screening method before performing FOB for patients with hemoptysis who have normal or nonspecific findings or peripheral airway disease in plain chest radiograph.

• Journal of Physiology & Pathology in Korean Medicine
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• 제17권3호
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• pp.666-671
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• 2003

Dental caries are the most commonly occurring chronic diseases in the dental field. Because of increasing sugar consumption and extension of average human life, these diseases are widely found all over the world as the most typical cause for a person to lose a tooth. Therefore, the development of more effective, substantial and safe preventive agents against dental caries is strongly required. Streptococcus mutans is known as the causative bacterial playing the most important role informing plaque and it is being noticed as major causative bacteria of dental caries. The present study was designed to investigate the effect of Asarum sieboldii Miquel(Aristolochiaceae) extracts on the growth, acid production, adhesion, and insoluble glucan synthesis of Streptococcus mutans(S. mutans). Both methanol and aqueous extracts showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 100, 1,000 and 2,000 μg/ml compared to the control group(p<0.05 - p<0.01). The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration of 10 μg/ml and complete inhibition was observed at the concentration of 2,000 μg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan from sucrose, methanol and aqueous extracts showed more than 70% inhibition over the concentration of 1,000 μg/ml. Hence, we conclude that Asarum sieboldii might be a candidate of anticaries agent.

• Korean Journal of Weed Science
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• 제32권2호
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• pp.98-106
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• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.

• Journal of Food Hygiene and Safety
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• 제35권2호
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• pp.146-151
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• 2020

This study investigated microbiological safety of employees' hands, dining tables, and indoor air in cooking areas and lunchrooms in child care centers. Microbiological tests were performed according to the Korea Food Code. Total numbers of aerobic bacteria and coliform bacteria were measured as 5.8±1.9 log CFU/hand and 4.0±2.4 log CFU/hand on employees' hands, and 4.3±3.0 log CFU/100 ㎠ and 2.6±3.3 log CFU/100 ㎠ on dining tables. Bacillus cereus were detected in two cases each of employees' hands and dining tables, respectively. The analysis of microbiological contamination of indoor air in chid care centers showed that the total numbers of aerobic bacteria and coliform bacterial were 28±7.2 CFU/plate and 3.1±2.9 CFU/plate, respectively. Bacillus cereus and Staphylococcus aureus were counted as 1.7±0.2 CFU/plate and 1.6±0.5 CFU/plate from the indoor air in child cate centers. These results indicate that indoor-air in child care centers is considered more safe compared to previous reports. In conclusion, it is necessary to carry out hygienic management using alcohol-based disinfectants before meals to remove microorganism contamination on dining tables and hands. In order to reduce microbial contamination in indoor air, it is also deemed necessary to freshen the sanitary caps, masks, and clothing of the catering staff with periodic ventilation of indoor air.

• Journal of The Korean Society of Grassland and Forage Science
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• 제39권4호
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• pp.227-234
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• 2019

This study was performed to investigate the effect of heat-stressed environment on rumen microbial diversity in Holstein cows. Rectal temperature and respiration rate were measured and rumen fluid was collected under normal environment (NE; Temperature humidity index (THI)=64.6) and heat-stressed environment (HE; THI=87.2) from 10 Holstein cows (60±17.7 months, 717±64.4 kg) fed on the basis of dairy feeding management in National Institute of Animal Science. The rumen bacteria diversity was analyzed by using the Illumina HiSeq^TM 4000 platform. The rectal temperature and respiratory rate were increased by 1.5℃ and 53 breaths/min in HE compared to that in NE, respectively. In this study, HE exposure induced significant changes of ruminal microbe. At phylum level, Fibrobacteres were increased in HE. At genus level, Ruminococcaceae bacterium P7 and YAD3003, Butyrivibrio sp. AE2032, Erysipelotrichaceae bacterium NK3D112, Bifidobacterium pseudolongum, Lachnospiraceae bacterium FE2018, XBB2008, and AC2029, Eubacterium celulosolvens, Clostridium hathewayi, and Butyrivibrio hungatei were decreased in HE, while Choristoneura murinana nucleopolyhedrovirus, Calothrix parasitica, Nostoc sp. KVJ20, Anabaena sp. ATCC 33047, Fibrobacter sp. UWB13 and sp. UWB5, Lachnospiraceae bacterium G41, and Xanthomonas arboricola were increased in HE. In conclusion, HE might have an effect to change the rumen microbial community in Holstein cows.

• Korean Journal of Organic Agriculture
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• 제21권3호
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• pp.391-401
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• 2013

This study was conducted to investigate feeding management and milk production in domestic organic dairy farms and find out ways to overcome difficulties in organic dairy farms. The number of domestic organic dairy farms was 35, which representing 0.57% among 6,068 of total dairy farms in 2011. Eleven farms among 35 organic dairy farms were surveyed. Average total raising head was 142, composed of 69 milk cow, 13 dry cow and 60 heifer and calf. The ratio of cow replacement was 42.4% in surveyed organic dairy farms. Among surveyed farms, 14.3% showed under 20kg of milk production, 57.1% represented 25~30kg of milk and 28.5% produced more than 30kg of milk. Average milk fat percentage in surveyed organic farms was 3.3%, which was lower than 4.04% milk fat percentage of whole country (2010). Based on bacterial counts (5,775 CFU/ml) and somatic cell counts (192,500 number/ml), milk quality appeared excellent in surveyed farms. 90% of surveyed farms agreed that organic milk production increased income. Among reasons for switching to organic dairy farm, environment-friendly farm management was the highest reason (54.5%). However, 45.5% of surveyed farms suffered difficulty in supply of organic feed. Therefore, stable supply of organic feed will be necessary to expand organic dairy farm in the future.

• Korean Journal of Breeding Science
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• 제43권3호
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• pp.201-205
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• 2011

'Hangangchal 1' is a new glutinous rice cultivar of second generation Tongil-type with a mid-maturing ecotype that developed by the rice breeding team of Yeongnam Agricultural Research Institute (YARI), RDA. in 2006. This cultivar was derived from a cross between 'Hangangchal', a Tongil-type glutinous cultivar and 'YR8208-20', a high yield potential in 1986/1987 winter season. 'Hangangchal 1' was selected by pedigree and bulk breeding methods from $F_3$ to $F_6$ populations. A promising line, YR10498-8-1-3, was selected and designated as 'Milyang 167' in 1997. The local adaptability test of 'Milyang 167' was carried out at seven locations during 3 years in 1998, 2005, and 2006. It has tolerance to lodging with good canopy architecture as 87cm of culm length. This cultivar is resistant to bacterial blight $K_1$, $K_2$, and $K_3$ race, rice stripe virus, rice dwarf virus, and leaf blast disease. The milled rice endosperm of 'Hangangchal 1' is glutinous and its whiteness was almost similar compared to 'Shinseonchalbyeo'. The yield of milled rice of 'Hangangchal 1' was average 5.97 MT/ha at ordinary cultivation of 9 kg/10a N fertilizer level in local adaptability test. This cultivar would be adaptable to the mid and southern plain of Korea.