• Journal of the Korean Geophysical Society
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• v.3 no.2
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• pp.113-126
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• 2000

We have conducted multiple geophysical surveys to investigate the geoenvironmental change of the Nanjido Landfill due to the stabilization process. Geophyscial surveys are comprized of gravity, magnetic, dipole-dipole electrical and SP methods. Due to the field conditions, surveys were conducted on the top surface of the landfill no.2 and southern border areas in front of landfills. The gravity anomalies obtained on the top surface of the landfill no.2 in 1999 show that the gradient of the anomaly on the central area is decreasing in comparison with that observed four years ago. The complexity of magnetic anomaly pattern it also decreasing. These facts suggest that the stabilization work of the Nanjido landfill makes some progress by compaction process due to repetitive subsidence and refilling. The dipole-dipole electrical resistivity and SP data obtained on the outside of the waterproof wall at the landfill no.1 were severely affected by unsatisfactory surface conditions. On the other hand, the dipole-dipole electrical resistivity profiles obtained on the inside and outside parts of the waterproof wall at the landfill no.2 show the blocking effect of leachate flow by the waterproof wall. Few SP anomalies are observed on the top and side surfaces of the landfill no.2, but SP anomalies obtained on the base area inside the waterproof wall strongly reflect the effect of leachate collecting wells.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.359-373
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• 1993

The ultimate objective of periodontal therapy is not only stopping the progression of periodontal disease, but also promoting the regeneration of lost periodontal tissue. Guided Tissue Regeneration, which is based on the principle that the goal of periodontal regeneration can be achieved by preventing apical migration of gingival epithelium and blocking cells originating from connective tissue, has been developed and used as a clinical procedure, and although it has shown excellent results in connective tissue healing, there have not been many studies showing its effect on the regeneration of alveolar bone loss due to periodontal disease. The objectives of this study are to investigate the result of 12 months-long treatment following guided tissue regeneration using expanded polytetrafluoroehylene membrane, and to observe the presence of regenerated alveolar bone. Forty-one teeth from 28 patients with clinical diagnosis of periodontitis has been selected. In fifteen of those interproximal intrabony defects, only flap operation had been carried out, and designated as the control group. Twenty-six intrabony defects received e-PTFE membrane following flap operation, and designated as the experimental group. Eleven teeth whose membrane had been exposed were excluded from the experiment. Various measurements including probing depth, loss of attachment, probing bone level and gingival recession have been recorded at 6th month and 12th month, and the significance of the changes has been analyzed. The results are as follows: 1. Probing depth at 6th and 12th month has shown a significant decrease in both groups (p<0.01), but significantly higher decrease was found in the experimental group compared to the control at the month(p<0.05). 2. Loss of attachment at 6th and 12th month has shown a significant decrease in both groups, but significantly higher decrease was found in the experimental group compared to the control (p<0.05). 3. Probing bone level at 6th and 12th month has shown a insignificant decrease in the control group and significant decrease in the experimental group (p<0.01). Significantly higher decrease in probing bone level was found in the experimental group (p<0.05). 4. Gingival recession at 6th and 12th month has shown a statistically significant increase (p<0.05), and the control group showed higher increase compared to the experimental group although no statistical significance was found. As these results have shown, the use of e-PTFE membrane in intrabony pockets results in marked decrease in the loss of attachment and probing bone level. This seems to indicate that e-PTFE membrane may play a role in alveolar bone regeneration in intrabony defects.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.669-676
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• 2007

The raw water was fractionated into hydrophobic (HPO), transphilic (TPI), and hydrophilic portions (HPI) using XAD resins. The raw water DOC contains 39% of hydrophilics, 43% of hydrophobics, and 18% of transphilics. When fractionated NOM (natural organic matter) was passed through hydrophilic membrane with 100 kDa, hydrophobic portion (HPO) caused the most fouling and hydrophilic portion (HPI) caused the least fouling. This could be related to size and adsorption capability of organics. Small sized organics would pass through membrane pores, but large sized organics would be attracted to either membrane pores or surface, which led to the fouling. An effect of membrane pore size on membrane fouling is related to the availability of organics at membrane pores. As the pore size became larger, the more organics were transported into the membrane pore. Some organics caused pore blocking, and others caused pore adsorption, which resulted in membrane fouling. Membrane material is also important for membrane fouling. More fouling occurred at hydrophobic membrane than hydrophilic membrane regardless of its pore size. Hydrophobic interaction caused more fouling at hydrophobic membrane.

• Journal of the Korean Chemical Society
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• v.54 no.2
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• pp.248-256
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• 2010

This study investigated the effects of the level of enrichment for analogies upon students' mapping, conceptual understanding, and the types of mapping errors in concept learning about Boyle's Law. Analogical reasoning ability test was administered and the score was used as a blocking variable. Three types (simple, enriched, and extended analogies) of learning materials according to the level of enrichment for analogies were studied by randomly assigned middle school students, and a conceptions test and a mapping test were administered immediately. The retention tests of both were administered four weeks later. Analyses of the results revealed that there was no main effect in the level of enrichment for analogies, but there was interaction effect with analogical reasoning ability in the post test on mapping. And the score of enriched analogy group was significantly higher than those of simple analogy group, but the score differences among three groups were not significant in the retention test on conceptual understanding. The frequency of the total mapping errors in the simple analogy group was the highest, and the frequencies of most types of mapping errors in the enriched and the extended analogy groups were less than those in the simple analogy group. There were also some differences in the frequencies of mapping errors with respect to the level of analogical reasoning ability. Therefore, these results will help science teachers plan and practice instructions using analogy.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.1
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• pp.63-66
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• 2008

Sunscreen is usually used by people when they are at the beach or outdoor swimming pools. Since the existing methods of and standards for measuring the effects of blocking ultra violet rays do not employ water resistance test methods, the establishment of a water resistance SPF test method is required. In this study, to standardize the SPF evaluation methods for a water resistant sunscreen, proposed measurement methods in this study were compared with those of foreign countries. Selected water resistance SPF experiments confirmed the product's suitability and a verification test was then conducted by establishing the variables of water resistance SPF measurement methods. In the comparative experiment on water resistance SPF given a water temperature of $23{\sim}32$ degrees centigrade showed that temperature did not have any statistically significant effect on water resistance SPF. The changing water flow also did not have any statistically significant effect on the water resistance SPF. Therefore, continuous 20 min water circulation is deemed appropriate as an alternative to the subject's usual activity.

• Restorative Dentistry and Endodontics
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• v.30 no.6
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• pp.470-476
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• 2005

The purpose of this Study was to invest)gate the function or calcitonin gene-related peptide (CGRP) in regulatory mechanism of pulpal microcirculation with the aim of elucidating neurogenic inflammation. Experiments were performed on twelve cats under general anesthesia. CGRP was administered through the femoral vein to see the systemic Influence and through the external carotid artery to see the local effect. Sympathetic nerve to the dental pulp was stimulated electrically and pulpal blood flow (PBF) was measured with a laser Doppler flowmeter on the canine teeth to the drug administration. The paired variables of control and experimental data were compared by paired t-test and differences with p < 0.05 were considered statistically significant. Systemic administration of CGRP $(0.3{\mu}g/ka)$ exerted decreases in systemic blood pressure and caused changes in PBF with an initial increase i311owed by decrease and a move marked second increase and decrease. Close intra-arterial (i.a.) injection of CCRP $(0.03{\mu}g/kg)$ resulted in slight PBF increase. The effect of CGRP resulted in no significant increase in PBF in the presence of $CGRP_{8-37}$. The electrical stimulation of the sympathetic nerve alone resulted in PBF decreases. The j.a. administration of CGRP following the electrical stimulation of the sympathetic nerve compensated the decreased PBF. Therefore, CGRP effectively blocked the sympathetic nerve stimulation-induced PBF decrease. Results of the present study have provided evidences that even though the local vasodilatory function of CGRP are weak, CCRP is effectively involved in blocking the vasoconstriction caused by sympathetic nerve stimulation in the feline dental pulp.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.686-702
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• 2021

BACKGROUND/OBJECTIVES: Schisandrae Fructus, the fruit of Schisandra chinensis Baill., has traditionally been used as a medicinal herb for the treatment of various diseases, and has proven its various pharmacological effects, including anti-inflammatory and antioxidant activities. In this study, we investigated the inhibitory effect of Schisandrae Fructus ethanol extract (SF) on inflammatory and oxidative stress in particulate matter 2.5 (PM2.5)-treated RAW 264.7 macrophages. MATERIALS/METHODS: To investigate the anti-inflammatory and antioxidant effects of SF in PM2.5-stimulated RAW 264.7 cells, the levels of pro-inflammatory mediator such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), cytokines including interleukin (IL)-6 and IL-1β, and reactive oxygen species (ROS) were measured. To elucidate the mechanism underlying the effect of SF, the expression of genes involved in the generation of inflammatory factors was also investigated. We further evaluated the anti-inflammatory and antioxidant efficacy of SF against PM2.5 in the zebrafish model. RESULTS: The results indicated that SF treatment significantly inhibited the PM2.5-induced release of NO and PGE₂, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. SF also attenuated the PM2.5-induced expression of IL-6 and IL-1β, reducing their extracellular secretion. Moreover, SF suppressed the PM2.5-mediated translocation of nuclear factor-kappa B (NF-κB) from the cytosol into nuclei and the degradation of inhibitor IκB-α, indicating that SF exhibited anti-inflammatory effects by inhibiting the NF-κB signaling pathway. In addition, SF abolished PM2.5-induced generation of ROS, similar to the pretreatment of a ROS scavenger, but not by an inhibitor of NF-κB activity. Furthermore, SF showed strong protective effects against NO and ROS production in PM2.5-treated zebrafish larvae. CONCLUSIONS: Our findings suggest that SF exerts anti-inflammatory and antioxidant effects against PM2.5 through ROS-dependent down-regulating the NF-κB signaling pathway, and that SF can be a potential functional substance to prevent PM2.5-mediated inflammatory and oxidative damage.

• Journal of Microbiology and Biotechnology
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• v.32 no.9
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• pp.1126-1133
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• 2022

This study investigated the contribution of lipoxygenase (LOX) inhibitors, nordihydroguaiaretic acid (NDGA), tetra-O-methyl nordihydroguaiaretic acid (M₄N) and zileuton (ZIL), and thromboxane A2 (TXA₂) inhibitor 4,5-diphenylimidazole (DPI) in the proliferation of Brucella abortus infection. None of the compounds affected the uptake of Brucella into the macrophages. We determined the effect of neutralizing leukotriene B4 (LTB4) receptor and showed that the uptake of the bacteria was inhibited at 30 min post-infection. M₄N treatment attenuated intracellular survival of Brucella at 2 h post-incubation but it was not observed in the succeeding time points. DPI treatment showed reduced survival of Brucella at 24 h post-incubation while blocking LTB4 receptor was observed to have a lower intracellular growth at 48 h post-incubation suggesting different action of the inhibitors in the course of the survival of Brucella within the cells. Reduced proliferation of the bacteria in the spleens of mice was observed in animals treated with ZIL or DPI. Increased serum cytokine level of TNF-α and MCP-1 was observed in mice treated with M₄N or ZIL while a lower IFN-γ level in ZIL-treated mice and a higher IL-12 serum level in DPI-treated mice were observed at 7 d post-infection. At 14 d post-infection, ZIL-treated mice displayed reduced serum level of IL-12 and IL-10. Overall, inhibition of 5-LOX or TXA₂ or a combination therapy promises a potential alternative therapy against B. abortus infection. Furthermore, strong ligands for LTB4 receptor could also be a good candidate for the control of Brucella infection.

• Journal of Life Science
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• v.32 no.6
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• pp.482-490
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• 2022

Sarcopenia, a geriatric and multifactorial syndrome characterized by progressive systemic skeletal muscle disorder, may be associated with many comorbidities. Sarcopenia caused by a decrease in muscle mass and muscle strength is accompanied by the aggravation of various pathological conditions, and as life expectancy increases, its prevalence will continue to increase in the future. During the aging process, chronic oxidative stress and increased inflammatory responses act as major contributors to skeletal muscle loss. In addition, disruption of autophagy and apoptosis signals associated with dysfunction of mitochondria, which are essential for energy metabolism, accelerates the loss of muscle proteins. The pharmacological effect of cordycepin, a major physiologically active substance in the genus Cordyceps, which has been widely used for the prevention and treatment of various diseases for a long time, is directly related to its antioxidant and anti-inflammatory actions. In this review, we present the correlation between apoptosis, autophagy, protein catabolism, and satellite cell activity important for muscle regeneration using cordycepin for the prevention and treatment of sarcopenia. Although there have been few studies so far on the use of cordycepin for sarcopenia, previous studies suggest that cordycepin may contribute to inhibiting the age-related weakening of mitochondrial function and blocking the breakdown of muscle proteins. In addition, the protective effect of cordycepin on muscle cell damage is considered to be closely related to its antioxidant and anti-inflammatory activities. Therefore, it is considered that more continuous basic research is needed, focusing on the molecular biological mechanism of cordycepin, which is involved in the anti-aging of muscle cells.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.305-310
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• 2023

This study aimed to determine the human androgen receptor (AR)-mediated endocrine disrupting potential of parabens and triclosan in food and household products using a cell-based assay in the OECD TG No.458, the 22Rv1/MMTV_GR-KO transcriptional activation assay. Four parabens (methyl-, ethyl-, propyl-, and butyl-) are determined as AR antagonists in OECD TG No.458. However, their AR antagonistic effects were not exhibited in the presence of the S9 hepatic fraction. Triclosan is also classified as an AR antagonist, and the AR antagonistic effect induced by triclosan significantly decreased in the presence of the phase I + II S9 fraction. Regarding the mechanism of AR antagonism induced by parabens and triclosan, the AR-mediated endocrine disrupting effects were exhibited through suppressing the translocation of ligand-bound AR to the nucleus via blocking of AR dimerization in the cytosol. These results indicate that the four parabens and triclosan have AR-mediated endocrine disrupting potential through an AR antagonistic effect via inhibiting AR dimerization; however, their endocrine disrupting effects deceased in the presence of hepatic metabolic enzymes.