• Food Science and Preservation
• /
• v.24 no.3
• /
• pp.325-333
• /
• 2017

This study aimed to investigate the various biological activities of Geranium thunbergii such as antimicrobial activity and protective effect against oxidative damage. To evaluate its antioxidant and antimicrobial activities, we first performed methanol extraction; this methanol extract was further partitioned using various solvents. And then, its antioxidant activity was measured using various assays including total phenolic content and protection against oxidative DNA damage, and antimicrobial activities were examined using minimum inhibiting concentration (MIC) test, and paper disc method. In addition, high-performance liquid chromatography was performed to analyze the major chemical components of ethyl acetate fraction. The G. thunbergii fraction with ethyl acetate exhibited higher antioxidant and antimicrobial activities than the other fractions. The results showed that G. thunbergii ethyl acetate fraction at $50{\mu}g/mL$ had strong DPPH and ABTS radical scavenging activities of 80.88% and 80.12%, respectively. In addition, the ethyl acetate fraction protected DNA from the oxidative damage induced by ferrous ion and hydroxyl radicals and showed high antimicrobial activity with diameter of inhibition zones ranging from 13.33 to 15.67 mm. High-performance liquid chromatography analysis revealed the major phenolic compounds of G. thunbergii to be ellagic acid and gallic acid. These results suggest that G. thunbergii might protect DNA against oxidative stress induced by reactive oxygen species and can be utilized as a natural source of antioxidant and antimicrobial agent in the food industry.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.3
• /
• pp.492-497
• /
• 2011

Soil management for orchard depends on the effects of soil microbial activities. The present study evaluated the soil microbial community of 25 orchard in Gyeongnam Province by fatty acid methyl ester (FAME) method. The average concentrations in the orchard soils were $332nmol\;g^{-1}$ of total FAMEs, $94nmol\;g^{-1}$ of bacteria, $46nmol\;g^{-1}$ of Gram-negative bacteria, $42nmol\;g^{-1}$ of Gram-positive bacteria, $4.8nmol\;g^{-1}$ of actinomycetes, $54nmol\;g^{-1}$ of fungi, and $9.1nmol\;g^{-1}$ of arbuscular mycorrhizal fungi. In addition, sandy loam soils had significantly low ratio of cy19:0 to 18:$1{\omega}7c$ compared with that of loam soils (p<0.05), indicating that microbial stress decreased. The average soil microbial communities in the orchard soils were 28.1% of bacteria, 15.9% of fungi, 13.6% of Gram-negative bacteria, 12.5% of Gram-positive bacteria, 2.8% of arbuscular mycorrhizal fungi, and 1.4% of actinomycetes. The soil microbial community of Gram-negative bacteria in peach cultivating soils was significantly higher than that of pear cultivating soils (p<0.05).

• Composites Research
• /
• v.34 no.5
• /
• pp.296-304
• /
• 2021

This study presented the evaluation of the stamp forming process for L-shape CF/PEKK thermoplastic composite using the finite element model. The formability of three different trimming allowances has been examined for representative product geometry. The results showed that those manufactured by high trimming allowance showed more excellent formability in those areas. Moreover, the effects of the trimming allowances on the stress, thickness, wrinkle distributions of thermoplastic composites fabricated with the stamp forming process were evaluated. The comparison of the simulation and experimental results for the thickness and wrinkle distributions proved the accuracy of the stamp forming model. The crystallinity of the composite was performed by differential scanning calorimetry (DSC). The void content of the composite was evaluated by matrix digestion. Then, the fabricated structure was characterized and achieved high quality in crystallinity and void content. Consequently, the presented FEM modeling shows excellent potential for application in the aircraft product design process. This pragmatic approach could efficiently offer a valuable solution for the thermoplastic composite manufacturing field.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.34 no.5
• /
• pp.263-270
• /
• 2021

In this study, a reliability-based design optimization of a 130-m class fixed-type offshore platform, to be installed in the North Sea, was carried out, while considering environmental, material, and manufacturing uncertainties to enhance its structural safety and economic aspects. For the reliability analysis, and reliability-based design optimization of the structural integrity, unity check values (defined as the ratio between working and allowable stress, for axial, bending, and shear stresses), of the members of the offshore platform were considered as constraints. Weight of the supporting jacket structure was minimized to reduce the manufacturing cost of the offshore platform. Statistical characteristics of uncertainties were defined based on observed and measured data references. Reliability analysis and reliability-based design optimization of a jacket-type offshore structure were computationally burdensome due to the large number of members; therefore, we suggested a method for variable screening, based on the importance of their output responses, to reduce the dimension of the problem. Furthermore, a deterministic design optimization was carried out prior to the reliability-based design optimization, to improve overall computational efficiency. Finally, the optimal design obtained was compared with the conventional rule-based offshore platform design in terms of safety and cost.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.4
• /
• pp.211-221
• /
• 2021

The Rabbit grass(Trifolium Repens, call it 'Clover') is a representative harmful plant of lawn, and it starts growing earlier than lawn, forming a water pipe on top of the lawn and hindering the photosynthesis and growth of the lawn. As a result, in competition between lawn and clover, clover territory spreads, but lawn is damaged and dried up. Damage to the affected lawn area will accelerate during the rainy season as well as during the plant's rear stage, spreading the area where soil is exposed. Therefore, the restoration of damaged lawn is causing psychological stress and a lot of economic burden. The purpose of this study is to distinguish clover which is a representative harmful plant on lawn, to identify the distribution of damaged areas due to the spread of clover, and to review of changes in vegetation before and after the eradication of clover. For this purpose, a time series analysis of three vegetation indices calculated based on images of convergence Drone with RGB(Red Green Blue) and BG-NIR(Near Infra Red)sensors was reviewed to identify the separation between lawn and clover for selective eradication, and the distribution of damaged lawn for recovery plan. In particular, examined timeseries changes in the ecology of clover before and after the weed-whacking by manual and brush cutter. And also, the method of distinguishing lawn from clover was explored during the mid-year period of growth of the two plants. This study shows that the time series analysis of the MGRVI(Modified Green-Red Vegetation Index), NDVI(Normalized Difference Vegetation Index), and MSAVI(Modified Soil Adjusted Vegetation Index) indices of drone-based RGB and BG-NIR images according to the growth characteristics between lawn and clover can confirm the availability of change trends after lawn damage and clover eradication.

• Journal of Korean Foot and Ankle Society
• /
• v.24 no.4
• /
• pp.135-141
• /
• 2020

Purpose: This study evaluated the results of two groups-the early group and midterm group-comparatively in the treatment of hallux valgus using a scarf osteotomy. Materials and Methods: From January 2005 to December 2009 (Group 1) and from January 2010 to December 2013 (Group 2), this study compared hallux valgus cases treated by a scarf osteotomy by a single surgeon with at least a five-year follow-up. Results: The average ages of Group 1 and Group 2 were 50.5 and 51.7 years old, respectively. The average follow-up of Groups 1 and 2 were 7.4 and 6.2 years, respectively. Groups 1 and 2 had 86 cases (53 patients) and 93 cases (64 patients) with at least a five-year follow-up, respectively. The average hallux valgus angle (HVA) and 1-2 intermetatarsal angle (IMA) of Group 1 were improved from 31.3° and 13.9° preoperatively to 11.3° and 6.8° at the final follow-up, respectively (p<0.001). The average HVA and 1-2 IMA of Group 2 were improved from 31.7° and 13.4° preoperatively to 8.9° and 6.6° at the final follow-up, respectively (p<0.001). The mean American Orthopaedic Foot and Ankle Society (AOFAS) score of both groups increased from 48.5 and 45.0 points preoperatively to 73.7 and 82.4 points at the final follow-up, respectively. The numbers of patient-assessed subjective satisfaction of Groups 1 and 2 at the final follow-ups were as follows: excellent, 27 and 36 (31.4%, 38.7%); good, 34 and 49 (39.5%, 52.7%); fair, 13 and 5 (15.1%, 5.4%); poor, 12 and 3 (13.9%, 3.2%); respectively. Neither troughing nor stress fractures occurred in both groups. Conclusion: Scarf osteotomy for treating hallux valgus is an excellent surgical method with a relatively low incidence of complications. The results in Group 2 were better than those in Group 1, showing that more surgical experience and evolution of the techniques provided better results.

• Journal of The Korean Society of Integrative Medicine
• /
• v.9 no.2
• /
• pp.83-92
• /
• 2021

Purpose : Keratinocytes are the main cellular components involved in wound healing during re-epithelization and inflammation. Dysfunction of tight junction (TJ) adhesions is a major feature in the pathogenesis of various diseases. The purpose of this study was to identify the various effects of a Sparassis crispa water extract (SC) on HaCaT cells and to investigate whether these effects might be applicable to human skin. Methods : We investigated the effectiveness of SC on cell HaCaT viability using MTS. The antioxidant effect of SC was analyzed by comparing the effectiveness of ABTS to that of the well-known antioxidant resveratrol. Reverse-transcription quantitative polymerase chain reaction (qRT-PCR) is the most widely applied method Quantitative RT-PCR analysis has shown that SC in HaCaT cells affects mRNA expression of tight-junction genes associated with skin moisturization. In addition, Wound healing is one of the most complex processes in the human body. It involves the spatial and temporal synchronization of a variety of cell types with distinct roles in the phases of hemostasis, inflammation, growth, re-epithelialization, and remodeling. wound healing analysis demonstrated altered cell migration in SC-treated HaCaT cells. Results : MTS analysis in HaCaT cells was found to be more cytotoxic in SC at a concentration of 0.5 mg/㎖. Compared to 100 µM resveratrol, 4 mg/㎖ SC exhibited similar or superior antioxidant effects. SC treatment in HaCaT cells reduced levels of claudin 1, claudin 3, claudin 4, claudin 6, claudin 7, claudin 8, ZO-1, ZO-2, JAM-A, occludin, and Tricellulin mRNA expression by about 1.13 times. Wound healing analysis demonstrated altered cell migration in SC-treated HaCaT cells and HaCaT cell migration was also reduced to 73.2 % by SC treatment. Conclusion : SC, which acts as an antioxidant, reduces oxidative stress and prevents aging of the skin. Further research is needed to address the effects of SC on human skin given the observed alteration of mRNA expression of tight-junction genes and the decreased the cell migration of HaCaT cells.

• Journal of Digital Convergence
• /
• v.19 no.7
• /
• pp.253-261
• /
• 2021

This study aims to confirm the association with the willingness to quit smoking in adult smokers with chronic diseases, and the research method was analyzed using data from the 7th National Health and Nutrition Survey (2016-2018). The subjects were frequency analysis, chi-square test, and logistic regression analysis of 960 chronically ill patients aged 19 years or older, which were analyzed using the SPSS 26.0 Program. As a result of the study, depending on the level of education, high school graduation (OR=1.328, 95%CI=1.004-1.757), college graduation or higher (OR=1.556, 95%CI=1.167-2.075), the more stressed you are (OR=1.602, 95%CI) =1.217-2.109), there was an attempt to quit smoking (OR=5.263, 95% CI=4.287-6.462), which was associated with the willingness to quit smoking. It is necessary to prevent chronic diseases by reducing the smoking rate through active participation in smoking cessation programs targeting groups with high willingness to quit smoking, and by preparing measures to relieve appropriate stress.

• Journal of Marine Life Science
• /
• v.4 no.2
• /
• pp.91-95
• /
• 2019

The changes of plasma cortisol concentration to high water temperature on common carp, Cyprinus carpio were studied. 20℃, 24℃ and 28℃ groups showed significantly increased plasma cortisol levels until 6 hours, and decreased plasma cortisol levels after 24 hours. Cortisol levels of 20℃ and 24℃ groups decreased to values close to the cortisol content before the experiment. However, 32℃ group showed significantly increased plasma cortisol levels until 24 hours, and maintained plasma cortisol level until 48 hours. The Cumulative mortality rates of 20℃, 24℃ and 28℃ groups increased until 12 hours, and maintained until 48 hours. Cumulative mortality rate of 32℃ group increased continuously until the end of the experiment. Using the results of this study, it could be used as a method to confirm the risk of mass perish in a specific area through hormone analysis.

• Journal of the Society of Disaster Information
• /
• v.15 no.2
• /
• pp.292-300
• /
• 2019

Purpose: To reduce the noise and vibration of reinforced concrete slab structures, the damping performance is to be performed experimentally after installing hollow core or filling it with liquid. Method: Using the hollow rate as an experimental variable, the damping ratio and stiffness of each test specimen at impact load are obtained to determine the difference between the damping ratio and stiffness of the numerical analysis. In addition, the damping effects are reviewed by comparing the difference in the damping ratio and stiffness of a test specimen filled with liquid 50% of the study. Results: Since the difference in resistance between a specimen with or without hollow core is 5%, it is judged that there is no structural problem, and the injection of liquid into the hollow core can increase the damping ratio, which can reduce noise or vibration. Conclusion: At less than 20% of hollow rate, there was little damping effect, and at 30%, damping effect was found. However, if liquid is injected into the hollow core of the specimen, damping rate is shown to increase, and the injection of liquid into the hollow part is believed to reduce noise or vibration.