• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.155-163
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• 2007

High Strength Concrete (HSC) has weakness that in a fire, it is spalled and brittles. The phenomenon of spalling is made by water vapor's (resulting from evaporation in the material at over $100{^{\circ}C}$)' being confined in watertight concrete. As the concrete strength increases, the degree of damage caused by the spalling becomes more serious because of the permeability. It is reported that the polypropylene(PP) fiber has an important role in protecting concrete from spalling and the optimum dosage of PP fiber is 0.2%. This study was conducted on the nonreinforced concrete specimens. The high-temperature behavior of high-strength reinforced concrete columns with various concrete strength and various dosage of PP fibers was investigated in this study. The results show that the ratio of unstressed residual strength of columns increases as the concrete strength increases and the ratio of unstressed residual strength of columns increases as the dosage of PP fiber increases from 0% to 0.2%, however, the effect of fiber dosage on residual strength of column barely changes above 0.2%.

• The Korea Journal of Herbology
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• v.39 no.4
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• pp.1-9
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• 2024

Objective : In this study, the anti-obesity effect of Fragaria orientalis (FO) on high-fat diet-induced obese mice was investigated. Drug treatment methods are widely used as obesity treatment methods, but research using various natural products is being conducted due to safety concerns. This study aims to evaluate the anti-obesity effect of FO extract, a natural product derived from Mongolia. Methods : C57BL/6 mice were used and divided into three groups, normal diet group, high-fat diet group, and high-fat diet with FO oral treatment group at a dose of 300 mg/kg. Extract was orally provided everyday for 6 weeks. Body Weight and food intake were measured every 2 days and blood lipid profiles and liver function in the sacrificed mice were evaluated. In addition, protein expression in hepatic tissue and histomorphological changes in liver and adipose tissue were observed. Results : Body weight, adipose tissue weight and FER were significantly lower in a high-fat diet with FO treatment than fed only high-fat diet. There was a significant difference between the high-fat diet and the FO-treated high-fat diet mice. As a result of analyzing lipid metabolism-related genes in hepatic tissue, all of p-AMPK, p-ACC, PPAR-α, CPT-1, and UCP-1 showed significant increases, and PPAR-γ also decreased significantly compared to the high-fat diet group. Conclusion : Overall, these results indicate that FO is effectual in improving obesity, suggesting that it can be used as a possible material for anti-obesity agents or functional supplements for weight control.

• Membrane and Water Treatment
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• v.15 no.3
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• pp.107-115
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• 2024

This study proposes the recycling of MVS as a value-added product for the removal of phosphate from aqueous solutions. By comparing the phosphate adsorption capacity of each calcined adsorbent at each temperature of MVS, it was determined that the optimal heat treatment temperature of MVS to improve the phosphate adsorption capacity was 800 ℃. MVS-800 suggests an adsorption mechanism through calcium phosphate precipitation. Subsequent kinetic studies with MVS-800 showed that the PFO model was more appropriate than the PSO model. In the equilibrium adsorption experiment, through the analysis of Langmuir and Freundlich models, Langmuir can provide a more appropriate explanation for the phosphate adsorption of MVS-800. This means that the adsorption of phosphate by MVS-800 is uniform over all surfaces and the adsorption consists of a single layer. Thermodynamic analysis of thermally activated MVS-800 shows that phosphate adsorption is an endothermic and involuntary reaction. MVS-800 has the highest phosphate adsorption capacity under low pH conditions. The presence of anions in phosphate adsorption reduces the phosphate adsorption capacity of MVS-800 in the order of CO 3 2-, SO 4 2-, NO 3- and Cl-. Based on experimental data to date, MVS-800 is an environmentally friendly adsorbent for recycling waste resources and is considered to be an adsorbent with high adsorption capacity for removing phosphates from aqueous solutions. This paper combines the advantages of gray predictor and AI fuzzy. The gray predictor can be used to predict whether the bear point exceeds the allowable deviation range, and then perform appropriate control corrections to accelerate the bear point to return to the boundary layer and achieve.

• Microbiology and Biotechnology Letters
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• v.52 no.1
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• pp.44-54
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• 2024

One of the serious modern environmental problems is pollution caused by highly toxic pesticides. Only small amounts of applied pesticides reach their target, and the rest ends up in soil and water. Chlorpyrifos is a toxic, broad-spectrum organophosphate insecticide. In humans, chlorpyrifos inhibits acetylcholinesterase (AChE) in the peripheral and central nervous system, and particularly in children, small amounts of this pesticide cause neurotoxic damage. As the toxic effects of chlorpyrifos and its persistence in the environment require its removal from contaminated sites, it is essential to study the biological diversity of chlorpyrifos-degrading microorganisms. In this study, we sought to determine the chlorpyrifos-degrading ability of the bacterial strain Ochrobactrum intermedium PDB-3. This strain was isolated from soil contaminated with various pesticides and identified as PDB-3 based on morpho-cultural characteristics, MALDI-TOF MS, and 16S rRNA. Studies were conducted for 30 days in sterile soils containing initial concentrations of 50, 75, 100, and 125 mg/kg of chlorpyrifos. To determine the degradation of chlorpyrifos, a liquid culture of the strain was added to the soil at three optical densities: 0, and after 24 and 48 h (OD = 0.03, 0.2 and 0.32). Using GX-MS, we determined that chlorpyrifos was converted to 3,5,6-trichloro-2-pyridinol (TCP). We also found that with increasing optical density, rapid degradation of the initial concentration of chlorpyrifos occurred. Sterile soil without strain PDB-3 was used as a control sample.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.5
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• pp.959-966
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• 2024

Recently, various IoT devices are being developed to suit the user's lifestyle in our daily lives. In this paper, a smart coffee machine using IoT technology was implemented through an application and an ESP-01 WiFi module. The implemented smart coffee machine is different from existing coffee machines with alarm functions in that it can manage the desired date and time with an application by combining IoT. The application uses Android Studio to input data and transmits appropriate information to the smart coffee machine. An Arduino-based circuit was configured to control the coffee machine and MP3 module so that coffee is extracted at the desired time and an alarm sound is heard through the speaker. The extracted coffee can be divided into three stages: hot, warm, and lukewarm depending on the temperature. Finally, the suitability of the implemented smart coffee machine was confirmed through an experiment on the change in coffee temperature according to the amount of water and time.

• Journal of Microbiology and Biotechnology
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• v.34 no.9
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• pp.1898-1911
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• 2024

Phylloporia lonicerae is an annual fungus that specifically parasitizes living Lonicera plants, offering significant potential for developing new resource food and medicine. However, wild resources and mycelium production of this fungus is limited, and its anti-tumor active ingredients and mechanisms remain unclear, hampering the development of this fungus. Thus, we optimized the fermentation medium of P. lonicerae and studied the anti-tumor activity of its mycelium. The results indicated that the optimum fermentation medium consisted of 2% sucrose, 0.2% peptone, 0.1% KH₂PO₄, 0.05% MgSO₄·7H₂O, 0.16% Lonicera japonica petals, 0.18% P fungal elicitor, and 0.21% L. japonica stem. The biomass reached 7.82 ± 0.41 g/l after 15 days of cultivation in the optimized medium, a 142% increase compared with the potato dextrose broth medium, with a 64% reduction in cultivation time. The intracellular alcohol extract had a higher inhibitory effect on A549 and Eca-109 cells than the intracellular water extract, with half-maximal inhibitory concentration values of 2.42 and 2.92 mg/ml, respectively. Graded extraction of the alcohol extract yielded petroleum ether phase, chloroform phase, ethyl acetate phase, and n-butanol phase. Among them, the petroleum ether phase exhibited a better effect than the positive control, with a half-maximal inhibitory concentration of 113.3 ㎍/ml. Flow cytometry analysis indicated that petroleum ether components could induce apoptosis of Eca-109 cells, suggesting that this extracted component can be utilized as an anticancer agent in functional foods. This study offers valuable technical support and a theoretical foundation for promoting the comprehensive development and efficient utilization of P. lonicerae.

• Journal of The Korean Society of Grassland and Forage Science
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• v.44 no.3
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• pp.215-219
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• 2024

Italian ryegrass (Lolium multiflorum Lam.) is one of the most widely grown winter forage crops in Korea, but its yields are known to be greatly affected by drought that occur frequently in spring. This study aimed to compare the growth and tolerance response characteristics to drought stress in several Italian ryegrass varieties cultivated in Korea. Twenty-day-old Italian ryegrass was subjected to drought treatment for 4 days, and then the growth and physiological responses of the plants were compared. Drought stress reduced leaf length, fresh weight, and dry weight in all Italian ryegrass varieties compared to the control. In addition, chlorophyll content was significantly decreased in all varieties treated with drought stress, but Fv/Fm was significantly decreased only in Winter hawk. For H₂O₂ and malondialdehyde (MDA) contents, Winter hawk showed the highest increase and New dawn showed the least increase. In terms of relative water content (RWC), New dawn showed the least decrease and Winter hawk showed the greatest decrease. These results indicate that New dawn is relatively drought-tolerant and Winter hawk is a drought-sensitive variety, indicating that each variety of Italian ryegrass has different drought tolerance mechanisms, which may provide basic insight for the development of tolerant varieties in the future.

• Anatomy and Cell Biology
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• v.55 no.3
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• pp.320-329
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• 2022

Aluminium exposure has been linked with developmental neurotoxicity in humans and experimental animals. The study aimed to evaluate the ameliorative effect of Tamarindus indica on the developing cerebellar cortex, neurobehavior, and immunohistochemistry of the cerebellar cortex following prenatal aluminum chloride (AlCl₃) exposure. Pregnant timed Wistar rats were divided into 5 groups (n=4). Group I (negative control) was given distilled water, group II was treated with 200 mg/kg of AlCl₃, group III were given 200 mg/kg of AlCl₃ and 400 mg/kg of ethyl acetate leaf fraction of Tamarindus indica (EATI), group IV were given 200 mg/kg of AlCl₃ and 800 mg/kg of EATI, and group V were treated with 200 mg/kg of AlCl₃ s/c and 300 mg/kg of vitamin E for 14 days (prenatal day 7-21) via the oral route. Male pups (n=6) were randomly selected and taken for neurobehavioral studies, and humanely sacrificed via intraperitoneal injection of thiopental sodium. The cerebellum was removed, fixed and tissue processed for histological and immunohistochemical studies. The results revealed that prenatal AlCl₃ exposure impacted neurodevelopment and neurobehaviour among exposed pups. Prenatal AlCl₃ exposure was marked with delayed cytoarchitectural development of the cerebellar cortex and increased GFAP expression in the cerebellar cortex. On the other hand, treatment with EATI and vitamin E were marked with significant improvements. The present study therefore concluded treatment with EATI shows an ameliorative effect to prenatal AlCl₃ exposure.

• Journal of Investigative Cosmetology
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• v.15 no.3
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• pp.263-273
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• 2019

The purpose of this study is to investigate antioxidant, whitening and anti-inflammatory effects of Centella asiatica extracts using supercritical extraction. In addition, Franz diffusion cell experiment was conducted using polymer micelle and cell permeation peptide for transdermal delivery. The DPPH radical scavenging test showed the highest DPPH radiated scavenging of C. asiatica water extract (CWE) and the SOD-like activity experiment represented that C. asiatica ethanol extract (CEE) was the highest SOD-like activity. However, C. asiatica supercritical extract (CSE) also showed good results in DPPH radical scavenging and SOD-like activity. In the inhibition test of melanin induced by α-MSH in B16 cells, CWE & CEE showed melanin inhibiting at high concentrations, but less than 20% at concentrations below 200 ㎍/mL. CSE represented melanin inhibiting at less than 50 ㎍/mL and almost 50% inhibition at the concentration. The inhibitory results of NO (nitric oxide) generation induced by LPS showed 88% by CWE at a concentration of 800 ㎍/mL compared to control treated only by LPS, 13% by CEE at a concentration of 200 ㎍/mL, 71% by CSE at a concentration of 100 ㎍/mL, and concentration-dependent increases in inhibits were found in CWE & CSE. For the skin permeability, in vitro experiment was conducted using polymer micelle and cell permeation peptide (R6) using the indicator material for CSE. The experiment showed that polymer micelle and cell permeation peptide effectively helped permeate the percutaneous tissue of CSE.

• Laboraroty Animal Research
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• v.35
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• pp.31-38
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• 2019

Although the number of prescriptions and dependence on sleeping pills are increasing, the associations with unexpected abnormal behaviors and metabolic diseases caused by the overuse of sleeping pills are not well understood. In particular, such as abnormal eating-behavior and the occurrence of metabolic disorders caused by psychological unstable states are reported. For this reason, herbal medicine, which has not had such side effects in recent years, is attracting attention as an alternative medicine/food for sleeping inducer. We have used ethanol extracts from Passiflora incarnata (PI) to steadily obtain positive effects on sleep and brain microenvironment. However, as mentioned earlier, sleep-inducing efficacy can only be used safely if the behavioral and metabolic abnormalities do not appear. Thus, in this study, we used Phenomaster equipment to continuously monitor the movement, feeding, water consumption, gas changes, etc. in C57BL/6 mice at a dose of 500 mg/kg/day for 5 consecutive days with PI extract group compared with the control group. Before sacrifice, differences in body composition of mice were also compared. Monitoring of 24 h/5 days through the equipment showed no change in PI-treated group in anything except for significant decrease in blood melatonin levels and activity after PI administration. Taken together, the statistically insignificance of any behavioral and metabolic phenomenon produced by repeated treatment of PI are not only expected to have an accurate sleep effect, but are also free of side effects of the prescribed sleeping pills. This study has given us greater confidence in the safety of the PI extracts we use for sleep-inducer.