• The Plant Pathology Journal
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• v.26 no.1
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• pp.57-62
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• 2010

Low-molecular-weight secondary metabolites from plants play an important role in reproductive processes and in the defense against environmental stresses or pathogens. In the present study, we isolated various volatiles and phenolic compounds from white Rosa rugosa flowers, and evaluated the pharmaceutical activities of these natural products in addition to their ability to increase survival in response to environmental stress and pathogen invasion. The DPPH and hydroxyl radical-mediated oxidation assay revealed that the white rose flower extract (WRFE) strongly scavenged free radicals in a dose dependent manner. Moreover, WRFE inhibited the growth of E. coli and fatally attacked those cells at higher concentration (>0.5 mg/mL). FITC-conjugated Annexin V stain provided further evidence that WRFE had strong antimicrobial activity, which may have resulted from a cooperative synergism between volatiles (e.g. 1-butanol, dodecyl acrylate and cyclododecane) and phenolic compounds (e.g. gallic acid) retained in WRFE. In conclusion, secondary metabolites from white rose flower hold promise as a potential natural source for antimicrobial and non-chemical based antioxidant agents.

• Mycobiology
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• v.38 no.4
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• pp.286-294
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• 2010

Epicoccum purpurascens stain 5615 AUMC was investigated for its biocontrol activity against root rot disease caused by Pythium irregulare. E. purpurascens greenhouse pathogenicity tests using three leguminous plants indicated that the fungus was nonpathogenic under the test conditions. The germination rate of the three species of legume seeds treated with a E. purpurascens homogenate increased significantly compared with the seeds infested with P. irregulare. No root rot symptoms were observed on seeds treated with E. purpurascens, and seedlings appeared more vigorous when compared with the non-treated control. A significant increase in seedling growth parameters (seedling length and fresh and dry weights) was observed in seedlings treated with E. purpurascens compared to pathogen-treated seedlings. Pre-treating the seeds with the bioagent fungus was more efficient for protecting seeds against the root rot disease caused by P. irregulare than waiting for disease dispersal before intervention. To determine whether E. purpurascens produced known anti-fungal compounds, an acetone extract of the fungus was analyzed by gas chromatography mass spectrometry. The extract revealed a high percentage of the cinnamic acid derivative (trimethylsiloxy) cinnamic acid methyl ester. The E. purpurascens isolate grew more rapidly than the P. irregulare pathogen in a dual culture on potato dextrose agar nutrient medium, although the two fungi grew similarly when cultured separately. This result may indicate antagonism via antibiosis or competition.

• Journal of Oriental Neuropsychiatry
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• v.21 no.2
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• pp.103-123
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• 2010

Objectives : This study was to investigate the effect of several herbal prescriptions such as Tianwangbuxindan qu zhusha, Tianwangbuxindan, Wendantang, Guipitang on the level of $MT_1$ and $MT_2$ melatonin receptors in C6 glial cells. Methods : For this study, we exposed of C6 cells to several herbal prescriptions resulted in non-cytotoxic in various dose as measured by MTT assay, trypan blue count, morphology change and DAPI stain. Results : Tianwangbuxindan qu zhush and Tianwangbuxindan induced the levels of $MT_1$ melatonin receptor expression in a dose-dependent manner without altering the level of $MT_2$ melatonin receptor expression. However, the treatment with Wendantang, Guipitang don't effect of $MT_1$ and $MT_2$ melatonin receptor expression. Conclusions : This results suggest that Tianwangbuxindan can be a promising the regulation of melatonin receptor synthesis, and further studies will be needed to clarify the mechanism.

• Structural Engineering and Mechanics
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• v.54 no.2
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• pp.199-219
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• 2015

This paper presents the non-destructive evaluation of a high-speed railway bridge using train-induced strain responses. Based on the train-track-bridge interaction analysis, the strain responses of a high-speed railway bridge under moving trains with different operation status could be calculated. The train induced strain responses could be divided into two parts: the force vibration stage and the free vibration stage. The strain-displacement relationship is analysed and used for deriving critical displacements from theoretical stain measurements at a forced vibration stage. The derived displacements would be suitable for the condition assessment of the bridge through design specifications defined indexes and would show certain limits to the practical application. Thus, the damage identification of high-speed railways, such as the stiffness degradation location, needs to be done by comparing the measured strain response under moving trains in different states because the vehicle types of high-speed railway are relatively clear and definite. The monitored strain responses at the free vibration stage, after trains pass through the bridge, would be used for identifying the strain modes. The relationship between and the degradation degree and the strain mode shapes shows certain rules for the widely used simply supported beam bridges. The numerical simulation proves simple and effective for the proposed method to locate and quantify the stiffness degradation.

• Journal of Species Research
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• v.9 no.4
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• pp.339-345
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• 2020

The Earth contains billions of microbial species, although the vast majority cannot be cultured in laboratories and are thus considered unidentified and uncharacterized. Extremophiles are microorganisms that thrive in extreme conditions, including temperature, salinity, and pH. Extremophilic microorganisms have provided important insights for biological, metabolic, and evolutionary studies. Between 2017 and 2019, as part of a comprehensive investigation to identify bacterial species in Korea, eight bacterial strains were isolated from marine and non-marine environments in Jeju Island. These strains were cultured under extreme salinity or pH conditions. Phylogenetic analysis using 16S ribosomal RNA(rRNA) gene sequencing indicated that all eight strains belonged to the phyla Gammaproteobacteria, Bacilli, and Alphaproteobacteria. Based on their high 16S rRNA gene sequence similarities(>98.7%) and the formation of strong monophyletic clades with their closest related species, all isolated strains were considered as an unrecorded strain, previously unidentified species. Gram stain reaction, culture conditions, colony and cell morphology, biochemical characteristics, isolation source, and National Institute of Biological Resources(NIBR) IDs are described in this article. The characterization of these unrecorded strains provides information on microorganisms living in Korea.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.1
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• pp.139-148
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• 1990

The purpose of this study was to investigate the effects of irradiation on the rat submandibular gland which composed of the epithelial growth factors. The experimental animals were the Sprague Dawley strain rats, which were the rats as the non-irradiated control group and the rats as the experimental group which were divided into groups as the experimental duration of 1 hour, 3 hours, 6 hours, 12 hours, 1 day, 3 days, 1 week, 2 weeks, 4 weeks. The experimental animals were singly irradiated at a dose of 8 Gray gamma ray to their head and neck region by the Co-60 teletherapy unit and sacrificed after each experimental duration. The specimens were stained with H-E and Azan stain and examined light microscopically. The results of this study were obtained as follows. 1. The all of mucous and serous acini in submandibular gland showed similar pattern of changes in structure according to the lapse of time. 2. The acinic cells started to change after 1 hour, and repaired after 12hours with mitosis and proliferation of the cells between acini. The changes were marked after 1day, and repaired gradually in course of time. 3. The duct were dilatated irregularly, and the outline of the eosinophilic stained ductal cells changed indistinctly.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.2
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• pp.257-263
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• 2011

This study was designed to investigate the effects of Hominis placenta pharmacopuncture treatment and electroacupuncture therapy on the functional recovery and histological change, protein expression in spinal cord injury(SCI) rats. Experimental groups were divided into the Group I(normal control rat), Group II(Non-treatment after spinal cord injury induction), Group III(Hominis placenta pharmacopuncture treatment after SCI induction), Group IV (Electroacupuncture therapy after SCI induction), Group V(Hominis placenta pharmacopuncture treatment and electroacupuncture therapy after SCI induction). After operation, rats were tested at modified Tarlov test at 1 to 3 days with divided into 4 groups, and motor behavior test(BBB locomotor rating scale, Grid walk test) was examined at 3, 7, 14, and 21 days. For the observation of damage change and size of the organized surface in muscle and spinal cord, histopathological studies were performed at 21 days by H & E stain, and BDNF & NT-3 protein expression studies were performed at 21 days. Acco rding to the results, Hominis placenta pharmacopuncture treatment and electroacupuncture therapy can play a role in facilitating recovery of locomotion following spinal cord injury. Specially, Hominis placenta pharmacopuncture treatment and electroacupuncture combimed therapy after SCI induction was most improvement in functional recovery, BDNF, and NT-3 protein synthesis.

• Smart Structures and Systems
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• v.5 no.1
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• pp.23-42
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• 2009

In order to reduce vibration or to control shape of structures made of metal or composites, piezoelectric materials have been extensively used since their discovery in 1880's. A recent trend is also seen to apply piezoelectric materials to flexible structures made of rubber-like materials. In this paper a non-linear finite element model using updated Lagrangian (UL) approach has been developed for static analysis of rubber-elastic material with surface-bonded piezoelectric patches. A compressible stain energy function has been used for modeling the rubber as hyperelastic material. For formulation of the nonlinear finite element model a twenty-node brick element is used. Four degrees of freedom u, v and w and electrical potential ${\varphi}$ per node are considered as the field variables. PVDF (polyvinylidene fluoride) patches are applied as sensors/actuators or sensors and actuators. The present model has been applied to bimorph PVDF cantilever beam to validate the formulation. It is then applied to study the smart rubber components under different boundary and loading conditions. The results predicted by the present formulation are compared with the analytical solutions as well as the available published results. Some results are given as new ones as no published solutions available in the literatures to the best of the authors' knowledge.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.67-68
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• 2019

Streptococcus constellatus is Gram-stain-positive, facultative anaerobic, and non-spore forming coccus. It is a member of normal flora of human oral cavity. S. constellatus KCOM 1039 was isolated from human postoperative maxillary cyst lesion. In this report, we present the draft genome sequence of S. constellatus KCOM 1039.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.271-276
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• 2007

Helicobacter pylori (H. pylori) infection is common in korea and high incidence at gastric ulcer and duodenal ulcer. $^{14}C-urea$ breath test ($^{14}C-UBT$) is regarded as a highly reliable and non-invasive method for the diagnosis of H. pylori infection. The purpose of this study was to evaluate the diagnositc performance of a new and rapid $^{14}C-UBT$, which was equipped with Geiger-Muller counter and compared the results with those obtained by gastroduodenoscopic biopsies (GBx). One hundred sixty-eight patients (M : F = 118 : 50) underwent $^{14}C-UBT$, rapid urease test (CLO test), and GBx. The results of $^{14}C-UBT$ were classified as positive (>50 cpm), borderline (25$^{14}C-UBT$ or CLO test results with GBx as a glod standard. In the assessment of the presence of H. pylori infection, the $^{14}C-UBT$ global performance yielded positive predictive value, negative predictive value and accuracy of 93.3% and 83.3%, respectively. However, the CLO test had performance yielded positive predictive value, negative predictive value and accuracy of 76.9%, 50.0%, respectively. In this study $^{14}C-UBT$ is a highly accurate, simple and non-invasive method or the diagnosis of follow up H. pylori infection.