• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.28-36
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• 2021

It is known that buried rebars inside concrete structures are protected from corrosion due to passive layer. It is very important to delay the timing of corrosion or evaluate a detection of corrosion initiation for the purpose of cost-beneficiary service life of a structure. In this study, corrosion monitoring was performed on concrete specimens considering 3 levels of cover depth(60 mm, 45 mm, and 30 mm), W/C(water to cement) ratio(40.0%, 50.0%, and 60.0%) and chloride concentration(0.0%, 3.5%, and 7.0%). OCP(Open Circuit Potential) was measured using agar-based socket type sensors. The OCP measurement showed the consistent behavior where the potential was reduced in wet conditions and it was partially recovered in dry conditions. In the case of 30 mm of cover depth for most W/C ratio cases, the lowest OCP value was measured and rapid OCP recovery was evaluated in increasing cover depth from 30 mm to 45 mm, since cover depth was an effective protection against chloride ion ingress. As the chloride concentration increased, the effect on the cover depth tended to be more dominant than the that of W/C ratio. After additional monitoring and physical evaluation of chloride concentration after specimen dismantling, the proposed system can be improved with increasing reliability of the corrosion monitoring.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.665-670
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• 2018

This study was designed to evaluate the physicochemical properties and biological activities (antioxidant activity and antimicrobial activities) of three and seven-year-old Platycodon grandiflorum extracts. Three and seven-year-old Platycodon grandiflorum contained crude saponins, free amino acids and minerals. Water extracts of the three and seven-year-old plants were prepared using reflux extraction methods. The total polyphenol contents (TPC), total flavonoid contents (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and antimicrobial effects of the extracts were determined. The seven-year-old Platycodon grandiflorum extract had higher TPC ($5.08{\pm}0.07TAEmg/g$) and TFC ($3.80{\pm}0.07QUEmg/g$). DPPH radical scavenging activity ($IC_{50}$ value: $288{\pm}3.88{\mu}g/mL$) and ABTS radical scavenging activity ($IC_{50}$ value: $568{\pm}2.09{\mu}g/mL$). The three and seven-year-old Platycodon grandiflorum extracts exhibited a strong antimicrobial effect against three kinds of bronchus disease-inducing bacteria; the seven-year-old Platycodon grandiflorum extracts showed a stronger antimicrobial effect than the three-year-old Platycodon grandiflorum extracts.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.121-138
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• 2019

In the present study, comparative efficacy of natural as well as synthetic tenderizers on the quality characteristics of restructured spent hen meat slices (RSHS) was studied. Four different batches of RSHS viz. Control (without any tenderizer), T1 (1.25% calcium chloride replacing salt in formulation), T2 and T3 (1.5% each of pineapple rind and fig powder, replacing binder in the formulation) were developed in pre-standardized formulation. Vacuum tumbling was performed for 2.5 h and cooked product (RSHS) was assayed for quality attributes. Samples were packaged in aerobic conditions, stored for 21 days under refrigeration ($4{\pm}1^{\circ}C$) and were evaluated for pH, oxidative and microbial quality parameters at regular interval of 7 days. Water holding capacity of T2 was recorded the highest and significantly higher (p<0.05) than all other samples. The textural attributes of T2 were comparable to T1 but significantly higher (p<0.05) than C and T3. The colour attributes ($L^*$, $a^*$, and $b^*$ value) of T2 and T3 were improved due to use of natural tenderizers. During sensory evaluation, tenderness scores for T2 samples were recorded the highest. Throughout storage period, thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA) and peroxide value (PV) followed an increasing trend for control as well as treated products; however, T2 showed a significantly (p<0.05) lower value than control and other treated samples. It can be concluded that good quality RSHS with better storage stability could be prepared by utilizing 1.5% pineapple rind powder as natural tenderizer.

• Food Engineering Progress
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• v.21 no.2
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• pp.132-137
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• 2017

The purpose of this study was to optimize dough properties using response surface methodology (RSM) and to demonstrate the performances of dough prepared under optimized conditions. Dough mixed with yeast, margarine, salt, sugar and wheat flour was prepared by fermentation process. Hardness, cohesiveness and springiness of dough were selected as critical quality attributes. The critical formulations (yeast and water) and process (fermentation time) variables were selected as critical input variables based on preliminary experiment. Box-Behnken design (BBD) was used as RSM. As a result, the quardratic, the squared and the linear model respectively provided the most appropriate fit ($R^2$>90) and had no significant lack of fit (p>0.05) on critical quality attributes (hardness, cohesiveness and springiness). The accurate prediction of dough characteristics was possible from the selected models. It was confirmed by validation that a good correlation was obtained between the actual and predicted values. In conclusion, the methodologies using RSM in this study might be applicable to the optimization of fermented foods containing various wheat flour and yeast.

• Journal of Nutrition and Health
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• v.54 no.5
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• pp.448-458
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• 2021

Purpose: Mulberry (Morus alba L.) fruit is widely grown in Asia and consumed as fresh fruit, jam, and juices. The fruit has beneficial health effects, including anti-diabetic, anti-tumor, and anti-obesity properties. However, the mechanisms by which mulberry fruit juice powder (MJ) regulates inflammatory microRNAs (miRs) are not yet known. This study investigated the effect of mulberry fruit juice powder on the regulation of inflammation and miR-132/143 during 3T3-L1 adipocyte differentiation. Methods: The 3T3-L1 cells were induced to differentiate for 2 days and then treated with various concentrations of MJ for 7 days. Cytotoxicity was determined by evaluating cell viability using a water-soluble tetrazolium salt-8 assay kit. Intracellular lipid accumulation was evaluated by oil-red O staining. The levels of the expression of genes involved in adipogenesis and inflammation, and miR-132/143 were measured by quantitative real-time polymerase chain reactions. Results: MJ showed no cytotoxic effect on 3T3-L1 adipocytes at concentrations below 100 ng/mL. Intracellular lipid accumulation was reduced by MJ treatment at concentrations of 100 ng/mL. The messenger RNA (mRNA) levels of proliferator-activated receptor-γ, cytosine-cytosine-adenosine-adenosine-thymidine/enhancer-binding protein-α, and adipocyte protein 2, which are involved in adipogenesis, were suppressed by MJ. A reduction was also seen in mRNA levels of genes related to the inflammatory response, such as tumor necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, and inducible nitric oxide synthase. The expression of the inflammatory miR-132 and miR-143 was also decreased by MJ. Conclusion: These results suggest that MJ may suppress adipogenesis and inflammation through the regulation of miR-132/143 expression in 3T3-L1 adipocytes. Thus, MJ may be useful as a food agent that prevents obesity-associated inflammation.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.2
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• pp.15-24
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• 2021

For the aquaculture industrialization of surf clam (Tresus keenae), it is important to basic data on the marine environment of the habitat of surf clam (T. keenae). In this study, we investigated the marine environment of habitat of surf clam (T. keenae) and sought to basic data for the preparation of surf clam (T. keenae) for artificial seed production. The water temperature of the habitat of surf clam (T. keenae) was the lowest in winter and appeared high in summer. The salt concentration showed it range from 31.2 to 33.9 psu. The pH showed it range from 7.69 to 8.70, with high pH in winter and low pH in summer. The dissolved oxygen(DO) was showed it range from 6.20 to 10.24 mg / L and the autumn was relatively higher than the spring and winter. The species composition of phytoplankton was about 30 to 40 species, and most of them were diatoms. The abundance of seasonal phytoplankton showed it range from 23.5 to 61.3 cells / ml, showing seasonal differences. The expression of dominant species also showed a difference depending on the season. As for the particle size composition of the sediment, sandy silt was the most distributed. Flow velocities appeared at 50-80 cm / s in the southeast direction at ebb tide and at 60-100 cm / s in the northwest direction at flood tide. The results of this study can be used as basic data for providing knowledge about the habitat and marine environment of surf clam (T. keenae) and for studying shellfish that inhabit the sedimentary layer.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.74.1-74.16
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• 2022

Background: Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood. Objectives: We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action. Methods: Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model. Results: In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model. Conclusions: We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.6
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• pp.23-32
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• 2022

Although PSCB girder bridges account for 4% of the bridges in use on highways, they do not account for much, but 98% of PSCB girder bridges are 1^st type and 2^nd type of bridge. Also, the total length of the PSCB girder bridge is 16% (192km) of the total length of the highway bridge. Thus, the PSCB girder bridge can be one of the bridge types where maintenance is important. In order to analyze the damage types of PSCB girder bridges, a detailed analysis was conducted by selecting 62 places (477 spans) precision safety diagnosis reports considering ratio of the construction method and snow removal environment exposure class. Analysis of report and a field investigation was conducted, and as a result, most of the causes of deterioration damage were caused by rainwater (salt water) flowing into the bridge pavement soaking in between the top flange and the interface. After concrete slab deteriorate occurred then bridge pavement cracking and breaking increased and exfoliation of concrete occurred by corrosion and expansion of the reinforcing bars occurred. In addition, the cause of cracks in the longitudinal direction on the bottom of the top flange is considered to be cracks caused by restrained drying shrinkage. In conclusion, for reasonable maintenance considering the characteristics of PSCB girder bridges, it should be suggested in the design aspect that restrained drying shrinkage crack on top flange. Also, it is believed that differentiated maintenance method should be proposed according to snow removal environment exposure class.

• Journal of Life Science
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• v.33 no.3
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• pp.234-241
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• 2023

At present, many countries around the world are legalizing cannabis and its products, and research on various treatments using cannabis is being actively conducted. However, the cannabis plant contains other compounds whose biological effects have not yet been established. We investigated the effect of cannabidiol (CBD) on hair growth in human dermal papilla cells (HDPCs). 2,2'-Azino-bis (3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays were performed to determine the antioxidant activity of CBD. The HDPCs viability of CBD was examined via water-soluble tetrazolium salt (WST-1) assay. The expression of hair-loss-related markers in HDPCs by CBD treatment was analyzed by real-time PCR and western blotting. The DPPH, ABTS radical scavenging activity assay showed that CBD had superior antioxidant activities. In HDPCs, CBD increased cellular proliferation at concentrations without cytotoxicity. It also increased the expressions of fibroblast growth factor 1 (FGF1), fibroblast growth factor 7 (FGF7), vascular endothelial growth factor (VEGF), and insulin-like growth factor (IGF). These results correlated with a decrease in the expression of inhibition-related factors, such as androgen receptor (AR) and transforming growth factor beta 1 (TGF-B1). Moreover, CBD resulted in a significant increase in the phosphorylation of AKT and extracellular signal-regulated kinase (ERK). Therefore, it is suggested that CBD may be a potential remedy for the treatment of alopecia.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.59-69
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• 2023

This study was carried for the purpose of using basic data for vegetation management plans by analyzing the current status of herbaceous community and Salix spp. community at Janghang Wetland in Han-river estuary. In order to investigate the vegetation status, the 50 plots were investigated and analyzed using the quadrat and Braun-Branquet method. In the herbaceous community, were found a total of 31 taxa of 11 families, 24 genera, 28 species, and 3 variants. A total of 42 taxa of 16 families, 33 genera, 39 species and 3 variants were appeared in the Salix subfragilis community, and a total of 46 taxa with classification of 19 families, 37 genera, 43 species, and 3 varieties were founded in the Salix koreensis community. As for the analysis of life-form and dominance, the hydatophytes was relatively high in the Salix subfragilis community, the hemicryptothytes was high in herbaceous community and therophytes was high in Salix koreensis community. As a result of correlation analysis of electrical conductivity(EC) and exchangeable sodium(Na+) in the soil, hydatophytes and hemicryptothytes showed a negative correlation, and therophytes showed a positive correlation. Therefore, it was analyzed that Salix koreensis and therophytes have a high rate of appearance in relatively dry and salty soil. Salix subfragilis, hydatophytes, and hemicryptothytes have a high rate of appearance in low salt concentrations and wet areas.