• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.768-773
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• 2014

In this study, experimental and numerical studies for the synthesis of carbon nanotube(CNT) in methane counterflow diffusion flame have been performed. Methane mixed with acetylene($C_2H_2$) was used as a fuel gas and ferrocene was used as a catalyst for synthesis of CNT. The major parameters was $C_2H_2$ mixing rate and mixing rates were 2 %, 6 %, and 10 %. Characteristics of CNT formation on grid were analyzed from SEM images. the chemical reaction mechanism adopted is GRI-MECH 3.0. Numerical results showed that flame temperature and CO mole fraction were increased with increasing acetylene mixing rate. Experimental results showed that the CNT synthesis in 2% acetylene mixture flame better than that of 6% and 10% acetylene mixture flames. It can be considered that 6% and 10% acetylene mixture flames generated the excessive carbon source and then it interrupted the supplement of the carbon source into ferrocene catalyst. It can be found that the supply of appropriate quantity of carbon source can make effect to synthesis of high purity of CNT.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.401-412
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• 2013

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.798-806
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• 2021

BACKGROUND/OBJECTIVES: Obesity is associated with chronic inflammation. The spleen is the largest organ of the lymphatic system and has an important role in immunity. Obesity-induced inflammatory responses are triggered by Toll-like receptor (TLR)-myeloid differentiation primary response 88 (MyD88) pathway signaling. Phenethyl isothiocyanate (PEITC) and 3,3'-diindolylmethane (DIM), major dietary glucosinolates present in cruciferous vegetables, have been reported to produce anti-inflammatory effects on various diseases. However, the effects of PEITC and DIM on the obesity-induced inflammatory response in the spleen are unclear. The purpose of this study was to examine the anti-inflammatory effects of PEITC and DIM on the spleen and their mechanism in high fat/cholesterol diet (HFCD)-fed C57BL/6 mice. MATERIALS/METHODS: We established an animal model of HFCD-induced obesity using C57BL/6 mice. The mice were divided into six groups: normal diet with AIN-93G diet (CON), high fat diet (60% calories from fat) with 1% cholesterol (HFCD), HFCD with PEITC 30 mg/kg/day or 75 mg/kg/day (HFCD+P30, HFCD+P75), and HFCD with DIM 1.5 mg/kg/day or 7.5 mg/kg/day (HFCD+D1.5, HFCD+D7.5). Enzyme-linked immunosorbent assay was used to evaluate pro-inflammatory cytokine secretion. Western blot and quantitative polymerase chain reaction were used to analyze protein and mRNA levels of nuclear factor kappa B (NF-κB) p65, interleukin 6 (IL-6), cyclooxygenase 2 (COX-2), TLR2, TLR4, and MyD88 in spleen tissue. RESULTS: Serum IL-6 levels were significantly higher in the HFCD group than in groups fed a HFCD with PEITC or DIM. Levels of NF-κB p65 protein and TLR2/4, MyD88, NF-κB p65, IL-6, and COX-2 mRNA were significantly higher in the HFCD group than in the CON group and were reduced by the PEITC and DIM supplements. CONCLUSIONS: PEITC- and DIM-supplemented diets improved splenic inflammation by modulating the TLR2/4-MyD88 pathway in HFCD-fed mice. We suggest that dietary glucosinolates may at least partially improve obesity-induced inflammation of the spleen.

• Animal Bioscience
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• v.34 no.10
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• pp.1590-1599
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• 2021

Objective: This study investigates the expression patterns of toll-like receptors (TLRs) and intracellular mediators in horse muscle cells after exercise, and the relationship between TLRS expression in stressed horse muscle cells and immune cell migration toward them. Methods: The expression patterns of the TLRs (TLR2, TLR4, and TLR8) and downstream signaling pathway-related genes (myeloid differentiation primary response 88 [MYD88]; activating transcription factor 3 [ATF3]) are examined in horse tissues, and horse peripheral blood mononuclear cells (PBMCs), polymorphonuclear cells (PMNs) and muscles in response to exercise, using the quantitative reverse transcription-polymerase chain reaction (qPCR). Expressions of chemokine receptor genes, i.e., C-X-C motif chemokine receptor 2 (CXCR2) and C-C motif chemokine receptor 5 (CCR5), are studied in PBMCs and PMNs. A horse muscle cell line is developed by transfecting SV-T antigen into fetal muscle cells, followed by examination of muscle-specific genes. Horse muscle cells are treated with stressors, i.e., cortisol, hydrogen peroxide (H₂O₂), and heat, to mimic stress conditions in vitro, and the expression of TLR4 and TLR8 are examined in stressed muscle cells, in addition to migration activity of PBMCs toward stressed muscle cells. Results: The qPCR revealed that TLR4 message was expressed in cerebrum, cerebellum, thymus, lung, liver, kidney, and muscle, whereas TLR8 expressed in thymus, lung, and kidney, while TLR2 expressed in thymus, lung, and kidney. Expressions of TLRs, i.e., TLR4 and TLR8, and mediators, i.e., MYD88 and ATF3, were upregulated in muscle, PBMCs and PMNs in response to exercise. Expressions of CXCR2 and CCR5 were also upregulated in PBMCs and PMNs after exercise. In the muscle cell line, TLR4 and TLR8 expressions were upregulated when cells were treated with stressors such as cortisol, H₂O₂, and heat. Migration of PBMCs toward stressed muscle cells was increased by exercise and oxidative stresses, and combinations of these. Treatment with methylsulfonylmethane (MSM), an antioxidant on stressed muscle cells, reduced migration of PBMCs toward stressed muscle cells. Conclusion: In this study, we have successfully cultured horse skeletal muscle cells, isolated horse PBMCs, and established an in vitro system for studying stress-related gene expressions and function. Expression of TLR4, TLR8, CXCR2, and CCR5 in horse muscle cells was higher in response to stressors such as cortisol, H₂O₂, and heat, or combinations of these. In addition, migration of PBMCs toward muscle cells was increased when muscle cells were under stress, but inhibition of reactive oxygen species by MSM modulated migratory activity of PBMCs to stressed muscle cells. Further study is necessary to investigate the biological function(s) of the TLR gene family in horse muscle cells.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.2
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• pp.43-57
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• 2021

The Forward Collision Warning, a representative technology of the Advanced Driver Assistance Systems, was selected as the target technology. The cognitive response time, deceleration, and impact were selected as the measures of effectiveness. And the amount of change with and without the Forward Collision Warning was measured. The experimental scenarios included a sudden stop event (1) of the vehicle in front of the driver and an event (2) in which the vehicle intervened in the next lane. All experiments were divided into day and night. As a result of the analysis, response time and the deceleration rate decreased when the forward collision warning system was installed. It was analyzed that the driver's risk situation could be detected quickly and the number of front-end collisions could be reduced as a result. Reflecting the driver's operating habits and diversifying the experimental scenarios will increase the installation effectiveness of ADAS and be used to estimate the effectiveness of other technologies.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.56-60
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• 2010

This study was carried out to develop of macro-protocol and the biosafety guide Golden Rice, modified vitamin A at large scale GMO field. Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in the environment and human health. Prior to GM plant release, applicants should provide the information on GM crops for approval. A total of $4,700m^2$ GM field, each of Golden Rice and 'Nakdong' were used for further analysis on agronomic traits and pathogenesis. Generally plant growth and panicle number in the transgenic lines were lower than in the wild type under field condition. The major agronomic traits such as plant growth, grain quality in Golden Rice were similar than in 'Nakdong'. The yield difference was due to reduced ripened rate and the 1,000 grain weight. The grain shape was similar donor plant, however, color of brown rice was different from segregation. Also the difference of pathogenesis reaction was not significant in the leaf blast and sheath blight between Golden Rice and 'Nakdong'. These results provided the agronomic data and pathogenesis for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.154-157
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• 2009

Pear has a gametophytic self-incompatibility (SI) system and its SI reaction is controlled by a single multi-allelic S-locus. 'Wonkyo Na-jasoojung 2' was selected from a cross between 'Wonwhang', early season major pear cultivar with high fruit quality and self-incompatible, and 92-18-79 (${S_4}^{sm}{S_4}^{sm}$) obtained from self cross of 'Osa-nijisseiki' (${S_2S_4}^{sm}$) (SM, stylar-part mutant), self-compatible bud mutant that originated from self-incompatible 'Nijisseiki' ($S_2S_4$) made in 2001 at the National Institute of Horticultural and Herbal Science, Rural Development Administration in Korea. '92-18-79' was selected as a self-compatible source through field investigation. It bloomed 1 day earlier than 'Osa-Nijisseiki' and similar to 'Wonwhang' in 2008. It is medium in tree vigor and spreading in tree habit. 'Wonkyo Na-jasoojung 2' is classified as highly susceptible to pear scab (Venturia nashicola) similar to 'Osa-Nijisseiki' and as resistant to black spot (Alternaria kikuchiana) similar to 'Wonwhang'. It had 65.7% fruiting rate by self pollination. The average optimum harvest time of 'Wonkyo Na-jasoojung 2' was 148 days after full bloom and it matured 2 days earlier than 'Osa-Nijisseiki' and 11 days later than 'Wonwhang'. The fruit is roundish oblate in shape and yellowish brown in skin color. Average fruit weight was 445 g and soluble solids content was 13.3 $^{\circ}Brix$. The flesh had abundant juice and negligible grit.

• Economic and Environmental Geology
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• v.52 no.2
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• pp.119-128
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• 2019

About 300,000 tones of oyster shell are annually produced in Korea and, thus, a massive recycling plan is required. Many desulfurizing studies using oyster shells with chemical composition of $CaCO_3$ have been performed so far; however, most of them have focused on dry desulfurization. This study investigates the possibility of using oyster shells for wet desulfurization after calcination. For this, a simulated wet desulfurization facility of spray type was devised and compared the SOx-stripping characteristics of calcined oyster shell with those of limestone. The calcined oyster shell slurry indicate a better desulfurizability than the slurries of raw shell or limestone because the oyster shell transformed to a more reactive phase ($Ca(OH)_2$) by the calcination and hydration. Because of this reason, when the calcined oyster shell slurries were used, the reaction residue showed the higher gypsum ($CaSO_4{\cdot}2H_2O$) contents than any other cases. In the continuous desulfurization experiments, calcined oyster shell slurry showed a wider pH variation than limestone or raw oyster shell slurries, another clear indication of high reactivity of calcined oyster shells for $SO_2$ absorption. Our study also shows that the efficiency of wet desulfurization can be improved by the use of calcined oyster shells.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.401-409
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• 2018

The purpose of this study was to examine the oral health care and self-rated health status of adults visiting dental clinics in the region of Busan and influential factors for their dental fear from January to May, 2017, in an effort to obtain some information on how to relieve fear. As for dental fear, adults who were in their 30s, who were homemakers and whose monthly income ranged from 4 to 4.99 million won. In regard to fear according to oral health care, dental fear caused by the treatment avoidance factor was stronger among the adults who didn't receive dental checkups and who brushed their teeth in the wrong way. Dental fear that was attributed to the physiological reaction factor and the stimuli-inducing factor was severer among the adults who didn't receive dental checkups and who had no scaling experience. Overall fear was severer among the adults who didn't receive dental checkups and who changed their toothbrushes every four or more months. The factors that affected dental fear were self-rated health status, self-rated oral health status, gender, age, whether to receive dental checkups on a regular basis or not, and oral health education experience. Therefore in order to alleviate dental fear, self-rated health status should be improved, and the kind of system that encourages regular dental checkups and provides oral health education should be prepared.

• Clean Technology
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• v.25 no.3
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• pp.238-244
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• 2019

In this study, the ignition characteristics of petroleum-based aviation fuel (Jet A-1), bio aviation fuel (Bio-6308), and blended aviation fuel (50:50, v:v) were analyzed in accordance with change of temperature and pressure. The ignition delay time of each aviation fuel was measured by combustion research unit (CRU) and the compositions of the fuels were analyzed by GC/MS and GC/FID for qualitative and quantitative results. From the results, it was confirmed that the ignition delay times of all aviation fuels were shortened with increasing temperature and pressure. In particular, the effect of temperature was larger than the effect of pressure. Also, the ignition delay time of Jet A-1 was the longest at all measurement conditions, and it was judged that this result is because of the structurally stable characteristics of the benzyl radical generated during the oxidation reaction of the aromatic compound (about 22.48%) in Jet A-1. Also, it was confirmed that Jet A-1 had no section where the degree of shortening of ignition delay time was decreased by increasing temperature, which was because the benzyl radical inhibits the response that can affect the negative temperature coefficient (NTC). The ignition characteristics of blended aviation fuel (50:50, v:v) showed a similar tendency to those of Jet A-1, rather than to those of Bio-6308, so that the blended aviation fuel (50:50, v:v) can be applied to the existing system without any change.