• Journal of the Korea Institute of Building Construction
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• v.15 no.3
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• pp.281-289
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• 2015

Carbonation of concrete causes reduction of pH and subsequently causes steel corrosion for reinforced concrete structure. However, for plain concrete structure or PC product, it can lead to a decrease in porosity, high density, improvement of concrete, shrinkage-compensation. Recently, based on this theory, research of $CO_2$ curing effect has been performed, but it was mainly focused on its effects on compressive strength using only ordinary portland cement. Researches on $CO_2$ curing effect for concrete containing $CO_2$ reactive materials such as ${\gamma}-C_2S$, MgO haven't been investigated. Therefore, this study has performed experiments under water-binder ratio 40%, and the replacement ratios of ${\gamma}-C_2S$ and MgO were 90%. Micro-chemical analysis, measurement of compressive strength according to admixtures and $CO_2$ curing were investigated. Results from this study revealed that higher strength was measured in case of $CO_2$ curing compared with none $CO_2$ curing for plain specimen indicating difference between 1.08 and 1.26 times, in case of ${\gamma}-C_2S$ 90, MgO 90 specimen, incorporating high volume replaced as much as 90%, it was proven that when applying $CO_2$ curing, higher strength which has difference between 14.56 and 45.7 times, and between 6.5 and 10.37 times was measured for each specimen compared to none $CO_2$ curing. Through micro-chemical analysis, massive amount of $CaCO_3$, $MgCO_3$ and decrease of porosity were appeared.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.114-121
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• 2019

This study evaluates the quality properties of soy-paste soybean cultivar for fermented soybean products. The six soybean varieties that include Jinpung, Saedanbaek, Daepung 2, Pyeongwon, Cheonga and Saeolkong were used in the experiment. The range of water uptake ratio, hardness after soaking and hardness after steaming were 117.00~131.33%, 1.65~3.30 kg and 0.05~0.14 kg, respectively. The physicochemical analysis indicated the following: Moisture content, 63.27~68.72%; pH, 6.43~6.60; total acidity, 0.27~0.45%. Color values for L value (lightness), a value (redness), and b value (yellowness) ranged from 39.07~67.92, 7.64~11.79, and 7.48~20.67, respectively. The amylase and protease activities of the Saedanbaek samples were the highest among all cultivars. The amount of viscous substance in the fermented soybean products by cultivars ranged from 5.93 to 8.37%, and Saedanbaek was the highest. The total viable cells counts for soybean fermented products were 9.11~9.42 log CFU/g. The amino-type nitrogen contents of all samples were in the range of 401.07 to 524.47 mg% and Saedanbaek cultivars showed the highest content (524.47 mg%). Based on the results, Saedanbaek will be suitable as a soy-paste soybean cultivar and the quality standards for the fermentation process of the fermented soybean products.

• Journal of Life Science
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• v.29 no.1
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• pp.52-59
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• 2019

The leave of Polygonum tinctorium (LPT) have been used for centuries as a traditional medicine and as a food ingredient and natural dye. The aim of the current study was to develop high-value added products using LPT. Hot water extract (HWE) and ethanol extract (EE) of LPT were prepared, respectively, and their bioactivity was evaluated. The extraction ratio for the HWE was 27.6%, which was two-fold higher than that of the EE. The contents of total polyphenol in the HWE and total sugar in the EE were 51.2 mg/g and 297.8 mg/g, respectively. The total flavonoid and reducing sugar contents were similar in the extracts, irrespective of the extraction solvent. The HWE did not show antimicrobial activity in a disc-diffusion assay, but the EE showed strong growth inhibition against gram-positive bacteria. The EE exhibited stronger DPPH and ABTS radical scavenging activities and reducing power than those of the HWE. The HWE was particularly effective as a scavenger of nitrite ($RC_{50}$ of $6.0{\mu}g/ml$). In an antithrombosis activity assay, the EE showed significant anticoagulation activity as determined by an extended blood coagulation time (thrombin time, prothrombin time, and activated partial thromboplastin time), in addition to platelet aggregation activity. The HWE also showed platelet aggregation inhibitory activity. This report provides the first evidence of antithrombosis activities of LPT. Our results suggest that LPT has potential as a new antioxidant and antithrombosis agent.

• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.591-599
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• 2023

Fisetin is a bioactive flavonol molecule and has been shown to have antioxidant potential, but its efficacy has not been fully validated. The aim of the present study was to investigate the protective efficacy of fisetin on C2C12 murine myoblastjdusts under hydrogen peroxide (H₂O₂)-induced oxidative damage. The results revealed that fisetin significantly weakened H₂O₂-induced cell viability inhibition and DNA damage while blocking reactive oxygen species (ROS) generation. Fisetin also significantly alleviated cell cycle arrest by H₂O₂ treatment through by reversing the upregulation of p21WAF1/CIP1 expression and the downregulation of cyclin A and B levels. In addition, fisetin significantly blocked apoptosis induced by H₂O₂ through increasing the Bcl-2/Bax ratio and attenuating mitochondrial damage, which was accompanied by inactivation of caspase-3 and suppression of poly(ADP-ribose) polymerase cleavage. Furthermore, fisetin-induced nuclear translocation and phosphorylation of Nrf2 were related to the increased expression and activation of heme oxygenase-1 (HO-1) in H₂O₂-stimulated C2C12 myoblasts. However, the protective efficacy of fisetin on H₂O₂-mediated cytotoxicity, including cell cycle arrest, apoptosis and mitochondrial dysfunction, were greatly offset when HO-1 activity was artificially inhibited. Therefore, our results indicate that fisetin as an Nrf2 activator effectively abrogated oxidative stress-mediated damage in C2C12 myoblasts.

• Physical Therapy Rehabilitation Science
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• v.13 no.1
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• pp.53-70
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• 2024

Background: The conventional deadlift is a popular exercise for enhancing trunk, core, and lower extremity strength. However, its use in sports medicine is constrained by concerns of lumbar injuries, despite evidence supporting its safety and rehabilitative benefits. To optimize muscle activation using resistive bands in variable resistance therapy, we explored their feasibility in the deadlift. Design: Comparative experimental design Methods: Surface electromyography recorded muscle activity in the trunk and lower extremities during lifting, with normalization to the isometric Floor Lift using Maximal Voluntary Contraction. Kinematics were measured using inclinometer sensors to track hip and trunk sagittal plane angles. To prevent fatigue, each subject only used one of the three pairs of bands employed in the study. Results: Our study involved 45 healthy subjects (mean age: 30.4 ± 6.3 years) with similar baseline characteristics, except for years of lifting and strength-to-years-of-lifting ratio. Various resistance band groups exhibited significantly higher muscle activity than conventional deadlifts during different phases. The minimal resistance band group had notably higher muscle activity in the trunk, core, and lower extremity muscles, particularly in the end phase. The moderate resistance band group showed increased muscle activity in the mid-and end-phases. The maximum resistance band group demonstrated greater muscle activity in specific muscles during the early phase and overall higher activity in all trunk and lower extremity muscles in the mid and end phases of the deadlift (p<0.05). Conclusion: Our findings provide valuable insights into muscle activation with various resistance bands during deadlift exercise in clinical and gym settings. There appears to be a dose-response relationship between increased resistance bandwidth, external load, myoelectric activation, and range.

• Korean Journal of Radiology
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• v.20 no.5
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• pp.854-861
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• 2019

Objective: To evaluate quantitative magnetic resonance imaging (MRI) parameters for differentiation of cysts from and solid masses in the anterior mediastinum. Materials and Methods: The development dataset included 18 patients from two institutions with pathologically-proven cysts (n = 6) and solid masses (n = 12) in the anterior mediastinum. We measured the maximum diameter, normalized T1 and T2 signal intensity (nT1 and nT2), normalized apparent diffusion coefficient (nADC), and relative enhancement ratio (RER) of each lesion. RERs were obtained by non-rigid registration and subtraction of precontrast and postcontrast T1-weighted images. Differentiation criteria between cysts and solid masses were identified based on receiver operating characteristics analysis. For validation, two separate datasets were utilized: 15 patients with 8 cysts and 7 solid masses from another institution (validation dataset 1); and 11 patients with clinically diagnosed cysts stable for more than two years (validation dataset 2). Sensitivity and specificity were calculated from the validation datasets. Results: nT2, nADC, and RER significantly differed between cysts and solid masses (p = 0.032, 0.013, and < 0.001, respectively). The following criteria differentiated cysts from solid masses: RER < 26.1%; nADC > 0.63; nT2 > 0.39. In validation dataset 1, the sensitivity of the RER, nADC, and nT2 criteria was 87.5%, 100%, and 75.0%, and the specificity was 100%, 40.0%, and 57.4%, respectively. In validation dataset 2, the sensitivity of the RER, nADC, and nT2 criteria was 90.9%, 90.9%, and 72.7%, respectively. Conclusion: Quantitative MRI criteria using nT2, nADC, and particularly RER can assist differentiation of cysts from solid masses in the anterior mediastinum.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.341-348
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• 2010

To investigate the effect of continual pre-plant application of liquid pig manure (LPM) on malting barley growth, quality and soil environment in double cropping system of rice and malting barley, the liquid pig manure was applied after harvesting rice and malting barley for 3 years. Field experiment was designed with non-fertilizer, chemical fertilizer (CF) recommended by soil testing, rice (LPM 50%+CF 50%)+malting barley (CF 100%), rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%), rice (LPM 100%)+malting barley (CF 100%) and rice (LPM 100%)+malting barley (LPM 100%). By continuous application of LPM 100%, the contents of available $P_2O_5$ and exchangeable K in the soil were increased. The available $P_2O_5$ increased from 243 to 350 mg $kg^{-1}$ and exchangeable K was changed 0.31 to 0.44 $cmol_{c}\;kg^{-1}$. However, the contents of available $P_2O_5$ and exchangeable K were not significant changes in rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%) plot. Bulk density of soil was not affected by application of LPM. The microbial density was high in order of bacteria > actinomycetes > fungi. The population of aerobic bacteria in rice (LPM 100%)+malting barley (LPM 100%) plot was higher than other plots. The ratio of aerobic bacteria/fungi and biomass C content were the highest in rice (LPM 100%)+malting barley (LPM 100%) plot. The yield of malting barley was increased 22% by increasing culm length, panicle length, No. of panicle and 1,000 grains as 358 kg $10a^{-1}$ in rice (LPM 100%)+malting barley (LPM 100%) plot compared with 294 kg $10a^{-1}$ in rice (CF 100%)+malting barley (CF 100%) plot. The content of ${\beta}$-glucan was low by 4.5 and 4.4% in non-fertilizer and rice (CF 100%)+malting barley (CF 100%) plot, respectively. The content of crude protein was the lowest by 8.2% in non-fertilizer and rice (CF 100%)+malting barley (CF 100%) plot and the quality of malting barley was good as within 11%.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.168-178
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• 1994

Acid sulfate soils occur extensively in Gimhae area where they have been formed from the brackish alluvial sediments along the sea coast and river estuary. The strong acid environment enhances silicate weathering and thus affects the soil clay minerals. The minerals were identified through chemical, X-ray diffraction and thermal methods. The ratio of $SiO_2$ and $Al_2O_3$ in the clay fractions ranged from 3.14 to 3.77, indicating that the distribution of the clay minerals were 1 : 1 and 2 : 1 minerals. Cation exchange capacity in the clay fractions was low due to high contents of 1 : 1 minerals and hydroxy interlayered vermiculite(HIV). The B and C horizon rich in jarosite have large amounts of yellow streaks which reflect high content of $Fe_2O_3$ and $K_2O$. Vermiculite and illite were quantified from thermogravimetry(TG), kaolin minerals from both TG and differential thermal analysis(DTA), and HIV from X-ray diffraction analysis. The dominant clay minerals were kaolin minerals, vermiculite, illite and HIV. HIV considered to be formed, especially, in acid soil environments. The minor minerals were quarts, feldspar, jarosite, pyrite, hematite and goethite. Kaolin minerals were the most abundant clay minerals throughout the acid sulfate soil. Kaolin minerals, however, increased towards the top of horizons throughout the soils and HIV decreased towards the top of horizons in the soil of Gimhae series and Haecheog series. Alteration of HIV to kaolin minerals during weathering of low pH condition in deep soil horizons may explain the high quantities of kaolin minerals and the relatively low quantities of HIV in the soil at top horizons.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.548-553
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• 2010

This study was carried out to compare the physicochemical characteristics of Korean traditional wines fermented by addition of sorghum (Sorghum bicolor) using different nuruks (SH and BS nuruk). The alcohol contents of the fermented wines ranged from 12.36 to 13.21%. The brix degrees of sorghum wines fermented using SH and BS nuruks were $8.6\sim17.9^{\circ}Bx$ and $7.6\sim20.0^{\circ}Bx$ on addition ratio, respectively. Wine no addedsorghum using SH and BS nuruks showed pH 3.74 and 3.40, total acidity of 1.40 and 1.51%, and 0.441 and 0.149 of turbidity. With increase of sorghum addition, brix degree, pH, turbidity and L-value decreased whereas total acidity and a-value increased. Total color difference (${\Delta}Eab$) parameters of wines fermented in 30, 70 and 100% sorghum addition using SH and BS nuruk were 4.33, 6.63 and 26.13, and 4.08, 5.29 and 10.59. Glucose content decreased with increasing amounts of sorghum. Organic acids such as lactic acid and acetic acid were predominantly detected in the fermented wine. Finally, based on sensory evaluations, the wine fermented by BS nuruk showed the best overall quality at 30% sorghum addition.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.169-182
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• 2014

This study investigates the physicochemical quality characteristics of tomato sauce added with different kinds of pimpinella brachycarpa. The results are as follows. The pH of tomato sauce added with freeze-dried pimpinella brachycarpa, in contrast to the tomato sauce with raw pimpinella brachycarpa, decreased as the addition quantity of the sample increased. As for sugar content, PBP0 with Pimpinella brachycarpa contained was shown to be the highest with 10.83. For chromaticity, all values (e.g, L, A and B) of tomato sauce added with pimpinella brachycarpa and with freeze-dried pimpinella brachycarpa decreased showing significant differences among the samples as the addition quantity of the samples increased. With increased addition quantity of the sample with freeze-dried Pimpinella brachycarpa, its water content decreased. PBP4, addition group with 4% of freeze-dried Pimpinella brachycarpa, was shown to be the highest DPPH free radical scavenging activity as 29.58. When adding Pimpinella brachycarpa to tomato sauce, a total number of micro-organisms decreased. In case of adding raw Pimpinella brachycarpa rather than freeze-dried Pimpinella brachycarpa, it created a further effect on an inhibitive action of growing and developing micro-organisms. In the preference of tomato sauce with Pimpinella brachycarpa, PBF2 with 2% of Pimpinella brachycarpa had the highest score as 5.1 for the color. For taste, 3.7, the lowest taste score, was shown in PBF1with 1% of Pimpinella brachycarpa. The overall preference revealed that PBF2 was the highest scoring 5.8.. PBF3 was scored highest with 5.9 for overall preference. From the comprehensive findings, 2~3% of the addition ratio between raw Pimpinella brachycarpa and freeze-dried Pimpinella brachycarpa in the production of tomato sauce is considered the most preferable.