• The Korean Journal of Physiology and Pharmacology
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• v.14 no.5
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• pp.257-263
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• 2010

Visnagin (4-methoxy-7-methyl-5H-furo[3,2-g][1]-benzopyran-5-one), which is an active principle extracted from the fruits of Ammi visnaga, has been used as a treatment for low blood-pressure and blocked blood vessel contraction by inhibition of calcium influx into blood cells. However, the neuroprotective effect of visnagin was not clearly known until now. Thus, we investigated whether visnagin has a neuroprotective effect against kainic acid (KA)-induced neuronal cell death. In the cresyl violet staining, pre-treatment or post-treatment visnagin (100 mg/kg, p.o. or i.p.) showed a neuroprotective effect on KA ($0.1{\mu}g$) toxicity. KA-induced gliosis and proinflammatory marker (IL-$1{\beta}$, TNF-${\alpha}$, IL-6, and COX-2) inductions were also suppressed by visnagin administration. These results suggest that visnagin has a neuroprotective effect in terms of suppressing KA-induced pathogenesis in the brain, and that these neuroprotective effects are associated with its anti-inflammatory effects.

• Journal of environmental and Sanitary engineering
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• v.19 no.3 s.53
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• pp.22-30
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• 2004

The extract with the dilution of $50\%$ ethanol and treatment of $121^{\circ}C$ for 15min were inhibited highly the growth of staph aureus, Ent. cloacae, Sh. sonnei, A. hydrophila, b. subtilis, St. faecalis and L. casei. of food samples, red-bean dregs with addition of extact of smilax china. leaves or sorbic acid took the similar inhibition effect to microorganisms for the early storage days(1-3days). There was inhibited the growth of microorganisms in strawberry Juice added to 20m1 of $1\%$ extract solution for one storage day in comparison with no addition of smilax china L. Over all with growth inhibition capability to microorganisms and foods, it was believed that the effect and value as the natural food preservatives and the extracts like as this natural plant material took the food safety and it was capable to develop the natural food preservation.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.7
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• pp.1013-1018
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• 2008

For a sequential port fuel injection natural gas engine, its combustion and emission characteristics at low loads are crucial to meet light duty vehicle emission regulations. Fuel injection timing is an important parameter related to the mixture formation in the cylinder. Its effect on the combustion and emission characteristics of a natural gas engine were investigated at 0.2 MPa brake mean effective pressure (BMEP)/2000 rpm and 0.26 MPa BMEP/1500 rpm. The results show that early fuel injection timing is beneficial to the reduction of the coefficient of variation (COV) of indicated mean effective pressure (IMEP) under lean burn conditions and to extending the lean burn limits at the given loads. When relative air/fuel ratio is over 1.3, fuel injection timing has a relatively large effect on engine.out emissions. The levels of NOx emissions are more sensitive to the fuel injection timing at 0.26 MPa BMEP/1500 rpm. An early fuel injection timing under lean burn conditions can be used to control engine out NOx emissions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.2
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• pp.135-142
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• 2008

Experimental studies on the aerodynamic coupling effect on natural frequencies, critical speed and flutter instability of rotating disks are investigated in this paper. The theoretical analysis uses a fluid-structure model where the aerodynamic effects are represented in terms of elastic, lift and damping and stiffness components. The experiments performed using a vacuum chamber and ASMO/DVD disks rotating in vacuum, open and enclosure in several gaps with stationary wall give three main results. One is that the aerodynamic effect by the surrounding air reduces the natural frequencies and critical speeds of the vibration modes. The second is that natural frequency of disks rotating in open air is larger than that in enclosure. Finally, it is shown that the disk vibration is reduced as the gap between the disk and the rigid wall decreases.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2107-2112
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• 2010

To analyze the effect of temperature on pavement types of dedicated lane, we have performed a temperature monitoring for pavements which were constructed in test track for Bimodal Tram. These pavements classified into four types; natural and artificial lawn, concrete and asphalt. Dedicated lane composed of natural and artificial lawn has a complex structure with concrete slab in contact surface of tires, and with 1m natural or artificial lawn in the middle part of lane. From monitoring results for pavements, dedicated lane with natural lawn shows lower temperature value compared with other dedicated lanes, and it is expected to decrease the heat island effect of conventional road if constructed.

• Bulletin of the Korean Chemical Society
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• v.2 no.2
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• pp.56-59
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• 1981

In this paper a further generalization of the theory of multilayer physical adsorption previously developed by the authors is attempted so that the effect of vertical interactions between adsorbent and adsorbate can be explicitly taken into account. In this attempt we have to discard the previously adopted assumption that the molecules in the second layer or above are all in the same physical state. In order to estimate the effect of vertical interactions on the adsorption isotherm the interaction energy between an adsorbed molecule and the adsorbent surface is assumd to vary as $r^{-3}$ where r is the distance that the molecule under consideration is separated from the adsorbent surface. Resulting adsorption isotherm is applied to interpret the adsorption data of tetramethylsilane vapor on iron film and good agreements between observed and calculated values are obtained over wide range of pressure.

• International Journal of Oral Biology
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• v.43 no.4
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• pp.193-200
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• 2018

The purpose of this study is to determine if natural extracts could be used as an additive in oral health food made with Weissella cibaria CMU (oraCMU). Natural extracts of green tea, mulberry leaf, licorice, and propolis, which are reported to have antimicrobial activities, were selected and used in this study. The minimum inhibitory concentrations (MIC) of extracts on periodontal pathogens such as Fusobacterium nucleatum and Porphyromonas gingivalis and their synergy effects with oraCMU by the fractional inhibitory concentrations methods were measured. From the results obtained, all the extracts showed no effect on the growth of oraCMU. Green tea extract showed the best antibacterial activity with MIC of 1.8 mg/ml against both F. nucleatum and P. gingivalis. In addition, green tea extract had a synergistic effect with oraCMU against F. nucleatum. Therefore, these results suggested that green tea extract is available as an additive in oral health food made with oraCMU.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.2
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• pp.300-311
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• 2024

Amid global environmental concerns, initiatives to adopt sustainable industrial processes have garnered significant attention in diverse sectors. Efforts have centered on utilizing natural resources as dyeing and functionalizing agents in the textile industry. However, the limited color fastness and functional endurance of natural compounds remains a substantial challenge. This research investigated whether ultrasound could enhance the finishing effect of natural compounds on cotton fabrics. Chestnut shell extract was prepared and applied to cotton fabrics using a pad-dry-cure technique, with concurrent application of ultrasonic power. Once integrated into the fabrics, the chestnut shell extract exhibited prolonged health benefits for users. The findings demonstrated that ultrasound treatment during the finishing process facilitated the diffusion of natural compounds from the chestnut shell extract into the fabric structure, resulting in a substantial enhancement of the finishing effect, notably augmenting the antibacterial properties of the treated cotton fabrics.

• Journal of Environmental Science International
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• v.27 no.6
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• pp.359-369
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• 2018

A model has been developed to predict natural ventilation in a single zone building with large openings. This study first presents pressure-based equations on natural ventilation, that include the combined effect of wind and thermal buoyancy. Moreover, the concept of neutral pressure level(NPL) is introduced to consider the two-way flow through a large opening. The total pressure differences across the opening and the NPL are calculated, and nonlinear equations are solved to find the zonal pressure to satisfy mass conservation. For this analysis, an iterative technique of successively approximating the zonal pressure is used. The results of applying this study model to several simple cases are as follows. When there is no wind and only the stack effect is caused, a one-way flow occurs in both the top and bottom openings in the case of two openings of equal-area, and a one-way flow occurs in the top opening; however, a two-way flow occurs in the bottom opening in the case of two openings of unequal-area. When there is a wind effect, regardless of whether the outside air temperature is lower or higher than the indoor air temperature, air flows into the room through the bottom opening and out of the room through the top opening. As the wind velocity increases, the wind effect appears to be more influential than the stack effect owing to the temperature difference.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1634-1636
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• 2009