• Journal of Radiation Protection and Research
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• v.25 no.3
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• pp.133-135
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• 2000

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.06a
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• pp.23-25
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• 2002

• 대한생식의학회:학술대회논문집
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• 2007.11a
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• pp.25-29
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• 2007

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.21 no.1
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• pp.19-25
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• 1992

• Journal of Periodontal and Implant Science
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• v.49 no.3
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• pp.138-147
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• 2019

Purpose: Several studies have shown that the oral cavity is a secondary location for Helicobacter pylori colonization and that H. pylori is associated with the severity of periodontitis. This study investigated whether H. pylori had an effect on the periodontium. We established an invasion model of a standard strain of H. pylori in human periodontal ligament fibroblasts (hPDLFs), and evaluated the effects of H. pylori on cell proliferation and cell cycle progression. Methods: Different concentrations of H. pylori were used to infect hPDLFs, with 6 hours of co-culture. The multiplicity of infection in the low- and high-concentration groups was 10:1 and 100:1, respectively. The Cell Counting Kit-8 method and Ki-67 immunofluorescence were used to detect cell proliferation. Flow cytometry, quantitative real-time polymerase chain reaction, and western blots were used to detect cell cycle progression. In the high-concentration group, the invasion of H. pylori was observed by transmission electron microscopy. Results: It was found that H. pylori invaded the fibroblasts, with cytoplasmic localization. Analyses of cell proliferation and flow cytometry showed that H. pylori inhibited the proliferation of periodontal fibroblasts by causing G2 phase arrest. The inhibition of proliferation and G2 phase arrest were more obvious in the high-concentration group. In the low-concentration group, the G2 phase regulatory factors cyclin dependent kinase 1 (CDK1) and cell division cycle 25C (Cdc25C) were upregulated, while cyclin B1 was inhibited. However, in the high-concentration group, cyclin B1 was upregulated and CDK1 was inhibited. Furthermore, the deactivated states of tyrosine phosphorylation of CDK1 (CDK1-Y15) and serine phosphorylation of Cdc25C (Cdc25C-S216) were upregulated after H. pylori infection. Conclusions: In our model, H. pylori inhibited the proliferation of hPDLFs and exerted an invasive effect, causing G2 phase arrest via the Cdc25C/CDK1/cyclin B1 signaling cascade. Its inhibitory effect on proliferation was stronger in the high-concentration group.

• International Journal of Oral Biology
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• v.34 no.2
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• pp.61-72
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• 2009

Chios gum mastic (CGM) is a resin produced from the stem and leaves of Pistiacia lentiscus L var chia, a plant which grows only on Chios Island in Greece. CGM has been used for many centuries as a dietary supplement and folk medicine for stomach and duodenal ulcers in many Mediterranean countries and is known also to induce cell cycle arrest and apoptosis in some cancer cells. In this study, we further investigated the induction and mechanisms underlying the apoptotic response to CGM treatment in the SCC25 human tongue squamous cell carcinoma cell line. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingival fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay, respectively. Staining with Hoechst and hemacolor dyes and TUNEL assays were employed to detect SCC25 cells undergoing apoptosis. SCC25 cells were treated with CGM, and this was followed by western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity analyses. CGM treatment of SCC25 cells was found to result in a time- and dosedependent decrease in cell viability, a dose-dependent inhibition of cell growth, and apoptotic cell death. Interestingly, CGM showed a remarkable level of cytotoxicity in SCC25 cells but not in normal cells. Tested SCC25 cells also showed several lines of apoptotic manifestation. Taken together, our present findings demonstrate that CGM strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and induces apoptosis via the proteasome, mitochondria and caspase cascades in SCC25 cells.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.6
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• pp.691-701
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• 2010

As the water-cycle is transformed by increasing of the impermeable area in process of urbanization, decentralized rainwater management facilities(infiltration, harvesting and retention facilities) as source control are considered to be a method of restoring water-cycle of urban and reducing runoff. SWMM model was used to analyse the change of water-cycle structure before and after development in A new town watershed. Modified SWMM code was developed to apply infiltration facilities. The modified SWMM was used to analyse the change of water-cycle before and after infiltration trench setup in AJ subcatchment. Changes of the impervious area by development and consequent increase in runoff were analyzed. These analyses were performed by a day rainfall during ten years from 1998 to 2007. According to the results, surface runoff increased from 51.85% to 65.25 %, and total infiltration volume decreased from 34.15 % to 21.08 % in A newtown watershed. If more than 80 infiltration trenches are constructed in AJ subcatchment, the low flow and the drought flow increases by around 47%, 44%, separately. The results of this study, infiltration trench is interpreted to be an effective infiltration facility to restore water-cycle in new town.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.335-342
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• 1994

This study was undertaken at Gowa, South Sulawesi, Indonesia, as part of a larger forage genetic resource evaluation project. The experimental program consisted of a field experiment where grass and legume species were grown in monocultures and the dry matter yield, rumen bag digestibility (RBDMD) and N content of leaf and stem components were monitored in the wet and dry seasons. Eight species of grass (Brachiaria decwnbens cv. Basilisk. Panicum maximum cv. Riversdale, Urochloa pullulans CPI 41192, Imperata cylindrica from Maiwa, South Sulawesi, Digitaria milanjiana CPI 41193, Cenchrus ciliaris cv. Malopo, Heteropogon contorlus and Setaria sphacelata cv. Splenda) were studied. P. maximum was the highest yielding grass in the wet season and B. decumbens in the dry season. The highest RBDMD in the whole plants were U. pulluians, P. maximum, S. sphacelata and D. milanjiana after 2 weeks regrowth in cycle I and S. sphacelata, B. decumbens, D. milanjiana and C. ciliaris in cycle 2. When total digestible DM was calculated for the whole of cycle I, P. maximum, B. decumbens and S. sphacelata were superior, but B. decumbens produced over twice as much as the other species in the dry season (cycle 2). The leaf N concentration of all grasses exceeded 1.0% (6.25% crude protein) in the regrowth in cycle I but did not exceed 0.5% in the dry season regrowth (cycle 2).

• Journal of Drive and Control
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• v.17 no.3
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• pp.15-25
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• 2020

The cycle time and power saving effect of a hydraulic hybrid injection molding machine using a servo motor are considered in this paper. In order to verify control characteristics, such as pressure and speed, experiments were performed with the hydraulic hybrid injection molding machine, clamping force of 110 ton. The power consumption and production cycle time of a conventional hydraulic injection molding machine were measured to compare its performances with the hydraulic hybrid injection molding machine. An injection molding machine with a clamping force of 1300 ton was used as the conventional machine, the hybrid machine was implemented by replacing its induction motors with servo motors. In the remodeled hybrid machine, experiments were performed to investigate how the displacement of the mold clamping pump affects the power consumption and production cycle time. The results showed that the production cycle time of the hybrid injection molding is similar to a conventional hydraulic injection molding machine but with a significant energy saving of about 40%.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.9
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• pp.630-639
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• 2007

A $CO_2$ cycle shows large throttling loss during the expansion process. The application of an expander into the $CO_2$ cycle can reduce the throttling loss and then improve system performance. In this study, the performance of a transcritical $CO_2$ cycle with an expander was analytically investigated in order to improve the cooling performance of the system. The expander was applied to the single-stage and two-stage compression cycles. The performance was analyzed with the variations of compressor frequency, outdoor temperature, and expander efficiency. The single-stage and two-stage compression cycles with the expander showed COP improvement of 25% and 32%, respectively, over the single-stage cycle with an EEV.