• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3581-3586
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• 2014

Aim: To investigate the effects of tetramethypyrazine (TMP) on proliferation and apoptosis of the human gastric carcinoma cell line 7901 and its possible mechanism of action. Methods: The viability of TMP-treated 7901 cells was measured with a 3-(4, 5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) and cell apoptosis was analyzed by flow cytometry. The distribution of cells in different phases of cell cycle after exposure of TMPs was analyzed with flow cytometry. To investigate the molecular mechanisms of TMP-mediated apoptosis, the expression of NF-${\kappa}Bp65$, cyclinD1 and p16 in SGC-7901 cells was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Results: TMP inhibited the proliferation of human gastric carcinoma cell line 7901 in dose and time dependent manners. Cell growth was suppressed by TMP at different concentrations (0.25, 0.5, 1.0, 2.0 mg/ml), the inhibition rate is 0.46%, 4.36%, 14.8%, 76.1% (48h) and 15.5%, 18.5%, 41.2%, 89.8% (72h) respectively. When the concentration of TMPs was 2.0mg/ml, G1-phase arrest in the SGC-7901 cells was significant based on the data for cell cycle distribution. RT-PCR demonstrated that NF-${\kappa}Bp65$ and cyclin D1 mRNA expression was significantly down-regulated in 7901 cells treated with 2.0 mg/ml TMP for 72h (p<0.05), while the p16 mRNA level was up-regulated (p<0.05). The protein expression of NF-${\kappa}Bp65$ and cyclin D1 decreased gradually with the increase in TMP concentration, compared with control cells (p<0.05), while expression of protein p16 was up-regulated (p<0.01). Conclusion: TMP exhibits significant anti-proliferative and pro-apoptotic effects on the human gastric carcinoma cell line SGC-7901. NF-${\kappa}Bp65$, cyclinD1 and p16 may also play important roles in the regulation mechanisms.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1123-1130
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• 2013

This paper aims to estimate work zone base capacity by the number of lanes for urban freeway. To do this, data were collected from the field survey and the database system maintained by traffic control center, and analyzed with four different methods such as the average maximum observation flow rate, headway, regression analysis, and parameter inspection. The work zone base capacity for urban freeway is estimated based on the average maximum observation flow rate and headway method, which are more reliable methods compared to others. The average capacity is 1,650pcphpl when the design speed is 80km/h. The capacity of four lanes one-way work zones was about 1,700pcphpl, while one of 2 lanes one-way work zones was about 1,600pcphpl. The capacity reduction rates for each are 0.15 and 0.2, respectively. The smaller the number of lane is, the more base capacity is reduced. For verification of results, we estimate the capacity by simulation analysis using PARAMICS, and compare with analytical results by a statistical method. This research can be used for efficient and systemic management of work zone in the urban freeway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.907-913
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• 2012

Piceatannol (trans-3,4,3',5'-tetrahydroxystilbene) is a polyphenol detected in grapes, rhubarb, and sugarcane. Although recent experimental data revealed that this compound is known to exhibit immunosuppressive and antitumorigenic activities in several cell lines, the molecular mechanisms underlying anticancer activity are poorly understood. In the present study, we investigated possible further mechanisms by which piceatannol exerts its anti-proliferative action in cultured human gastric cancer AGS cells. Piceatannol treatment resulted in the inhibition of growth and G1 arrest of the cell cycle in a concentration-dependent manner, as determined by MTT assay and flow cytometry analysis. The induction of G1 arrest by piceatannol was associated with the modulation of cyclin-dependent kinases (Cdks) and cyclins, up-regulation of the expression of Cdk inhibitor p21 (WAF1/CIP1) in both transcriptional and translational levels, and the inhibition of phosphorylation of retinoblastoma proteins and E2F1 expression. In addition, piceatannol treatment caused a progressive decrease in the expression levels of cyclooxygenase (COX)-2 without significant changes in the levels of COX-1, which was correlated with a decrease in prostaglandin $E_2$ synthesis.

• Restorative Dentistry and Endodontics
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• v.35 no.3
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• pp.173-179
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• 2010

The purpose of the present study was to compare the influence of post-surface treatment with silane, hydrogen peroxide, hydrofluoric acid or sandblasting and to investigate the effect of silane in combination of the other treatments on the microtensile bond strength between fiber posts and composite resins for core build-up. Thirty-two glass-fiber posts (FRC Postec Plus, Ivoclar Vivadent, Schaan, Liechtenstein) were divided into eight groups according to the different surface pretreatments performed: silane application (S); immersion in 28% hydrogen peroxide (HP); immersion in hydrogen peroxide followed by application of silane (HP-S); immersion in 4% hydrofluoric acid gel (HF); immersion in hydrofluoric acid gel followed by application of silane (HF-S); sandblasting with aluminum oxide particles (SB); sandblasting followed by application of silane (SB-S). In control group, no surface treatment was performed. The composite resin (Tetric Flow, Ivoclar Vivadent, Schaan, Liechtenstein) was applied onto the posts to produce the composite cylinder specimen. It was sectioned into sticks to measure the microtensile bond strength. The data was analyzed with one-way ANOVA and LSD test for post hoc comparison (p < 0.05). Post pretreatment with sandblasting enhanced the interfacial strength between the fiber posts and core materials. Moreover, sandblasting followed by application of silane appears to be the most effective method that can improve the clinical performance of glass fiber posts.

• Journal of Distribution Research
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• v.15 no.5
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• pp.61-79
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• 2010

As the interest and the importance of environmental protection increases rapidly, the environment considers to be not only the item that requires a control and a duty fundamental element but the fundamental element to enhance the internection icompetitiveness n so. Along with the collapse of the foreign trade barrier and the quality improvement of a customer's life qu life of a an object is shortened liforder to sectsfy the customer's lemands and as the result of it quaother critical issues rmparding the waste treatment and recasles are now thought to be momentou onlyaddition to the issue of the greenhou e gases reduction that is considered as one of me q issues among many internection ienvironmental issues. To keep up the pace with the environmental flow qube notd countries have nlreal iput their attempts to solve this environmental problems through a number of rmpulactios and acctios and they have showed a great concern for it as it is an internection iproblem that they should aasroaeronlythe aspect of not just a compan isr a country but of the wte e globn ivillage. Sueroenvironmental flow alemaned the logistic stratmpy of a compan iand it brought up the demand for the reverse logistics in a supply chain. For the reason above, the concept of reverse logistics and classification, the comparison with any similar concepts and its necessity are studied in this research through the theoretical consideration and the current state of the reverse logistics is organized in this research by acknowledging the domestic development process and the properties regarding the recycles of resources. In addition, the way to apply to the nation was investigated by comparing with the environmentalism development process, the reverse logistics policies and examples of advanced countries in logistics. The research proposed building of intimate cooperative system between a shipper and logistic service provider for the reverse logistics throughout the whole supply chain, the financial support, amendment of regulations, support Eco-friendly logistic technology development and the propagation, effective logistic system development and others and it is expected to bring a significant meaning to the reverse logistic policy and operation later on.

• Journal of Korea Water Resources Association
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• v.49 no.2
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• pp.95-106
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• 2016

Water Management Resilience Index (WMRI) was developed as a policy measure of adaptability to withstand water stresses and to set up water management strategies mainly in mid-small scale tributaries, and then evaluated on 117 sub-basins in South Korea. The index consists of 3 sub-indices such as vulnerability, robustness and redundancy sub-indices, each including indicators of 3 sectors: water use, flood mitigation, and river environment. Total number of indicators selected for the index was 31. Taking into account the stream order and control capability of river flow discharge, sub-basins were categorized into 3: 1 for mainstreams of lower large dams, 2 and 3 for tributaries, respectively without and with flow discharge regulation. As a result of the evaluation, resilience index scores in Category 2 and 3 are much lower than that of Category 1, especially with very poor score of redundancy. Although there was no significant difference between mainstream and tributaries in vulnerability and robustness sub-indices, results of redundancy sub-index in tributaries were lower than those in mainstream. Thus, it is conceived that the variety of water management schemes should be considered to improve their resilience in the face of future uncertainty. Addressing comprehensive stability of river basin against internal and external impacts, WMRI in this study can also be used for the prioritization of water management plans.

• Journal of Korea Water Resources Association
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• v.49 no.2
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• pp.83-94
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• 2016

Geomorphological, bed material and hydraulic characteristics are basis informations for the planning, design and management of the river in the aspect of flood control and environmental conservation, and it is very important to use these informations for the design of stable channel. In this study, dominant discharge was selected, geomorphological and hydraulic characteristics were analyzed using that discharge and also the characteristics of bed materials distribution were analyzed and bed materials-flow resistance relationship was evaluated, for the upstream section of Namgang dam. The dominant discharge was estimated a return period of approximately 1.5 year and stream type were classified Segment 1 and Segment 2 in this stream. Also, the frequency of riffle-pool showed 4.4 because this study area has the characteristics of natural channel that have not channel-crossing structures. In dominant discharge, according to the results that analyzed relationship between $h/d_{50}$ and $V/u_*$ to calculate flow resistance by bed materials, Julian's formula showed to appropriate in channel where is relatively close to natural river and is predominantly consisted of gravel, cobble, boulder and rock in mountain, and it was confirmed that the image processing methodology will be easily applied to the analysis of bed materials distribution in future.

• Journal of Korea Water Resources Association
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• v.46 no.7
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• pp.719-733
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• 2013

In this study, a watershed-based surface-water and groundwater integrated model, SWAT-MODFLOW was used to evaluate streamflow depletion induced by groundwater withdrawals and irrigation reservoirs for the Juksan-cheon watershed in South Korea. The streamflow responses to groundwater pumping and irrigation reservoirs were simulated under several different scenarios. The scenarios were (1) current pumping well withdrawals with reservoirs; (2) current pumping well withdrawals without reservoirs; (3) no pumping well withdrawals with reservoirs; (4) no pumping well withdrawals without reservoirs (natural condition). The simulated results indicated that the effects of groundwater pumping on streamflow depletion are a little more significant than those of irrigation reservoirs. Particularly, the groundwater withdrawals with irrigation reservoirs at current status (scenario 1) has induced the decrease of more than 20% in drought flow against the natural condition (scenario 4) at the outlet of the watershed. The specific drought flows through the main stream of Juksan-cheon watershed were simulated in order to assess the irrigation effects on downstream flows. It was found out that the specific drought flows are increasing as the distance from the reservoir increases due to the accumulation of the return flows to stream.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.174-182
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• 2006

This study was to clarify the effects of forest stand changes on hydrological components of evapotranspiration and discharge. The forest-hydrological experimental stations in Gwangneung and Yangju, Gyeonggido near metropolitan Seoul have been operated by the Korea Forest Research Institute since 1979 to clarify the effects of forest types and practices on the water resources and nutrient cycling and soil loss. The hydrological regime of the forested catchments may change as forests develop. The ranges of change may be different depending on forest types. Evapotranspiration can be estimated to 679mm, 580mm and 368mm in planted young coniferous (PYC), natural old-growth deciduous (NOD) and rehabilitated young mixed (RYM), respectively. The slope of the discharge-duration curve shows the capacity of discharge control in a specific catchment. The slope tended to be steeper in RYM than NOD, the better forest condition. The slope in RYM became more gentle as the forest stand developed. Forests can modulate peak flows through interception, evapotranspiration and soil storage opportunity. PYC and RYM showed 100 and 50mm of threshold rainfall for modulating peak flows, respectively. The deciduous forest did not represent sudden changes of peak flow rates to rainfall, even 200 mm rainfall Forest development in PYC may play an important role in modulation of peak flows because peak flow rates reduced after 10 years.

• Journal of Energy Engineering
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• v.16 no.1 s.49
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• pp.32-39
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• 2007

Coal pyrolysis processes vary with the origin and rank of coal. It is difficult to generalize the characteristics of coal pyrolysis reaction because the process consists of numerous reactions including pyrolysis, gasification, and combustion. To find out the optimum process condition it is necessary to determine the condition fur each coal from the smatter scale experiment. In this study pressurized ($2kg_{f}/cm^{2}$) fluidized bed, low temperature ($735{\sim}831^{\circ}C$) gasification using Kideco coal was performed. The reaction condition and product gas composition were determined from the variables including steam flow rate, coal feed rate and air flow rate. Optimum reaction condition was determined from the concentrations of $H_{2}$, and CO in the product gas. The ratio of air/coal was 4.45 and that of steam/coal was 0.21 respectively. The concentrations of CO and $H_{2}$ decreased with the increase of $CO_{2}$. It is important to control the feed rates of coal and steam because the reaction temperature rapidly increased when the combustion reaction dominates over the gasification reaction. The concentrations of CO and $H_{2}$ were 18%, 17% respectively from the continuous operating condition.