• International Journal of Oral Biology
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• 제43권2호
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• pp.69-76
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• 2018

Oral squamous cell carcinoma (OSCC) is the most common type of oral malignancy. Numerous therapies have been proposed for its cure. Research is continually being conducted to develop new forms of treatment as current therapies are associated with numerous side-effects. Luteolin, a common dietary flavonoid, has been demonstrated to possess strong anti-cancer activity against various human cancer cell lines. Nevertheless, research into luteolin-based anticancer activity against oral cancer remains scarce. Thus, the objective of this study was to assess the effect of luteolin as an anti-cancer agent. After treatment with luteolin, Ca9-22 and CAL-27 oral cancer cells showed condensed nuclei and enhanced apoptotic rate with evidence of mitochondria-mediated apoptosis. Epithelialmesenchymal transition (EMT) is closely related to tumor migration and invasion. Luteolin suppressed cancer cell invasion and migration in the current study. Elevated expression of E-cadherin, an adherens junction protein, was evident in both cell lines after luteolin treatment. Luteolin also significantly inhibited transcription factors (i.e., N-cadherin, Slug, Snail, Twist, and ZEB-1) that regulated expression of tumor suppressors such as E-cadherin based on Western blot analysis and quantitative PCR. Thus, luteolin could induce mitochondrial apoptosis and inhibit cancer cell invasion and migration by suppressing EMT-induced transcription factors.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.17-28
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• 2010

As a preliminary survey to improve efficiency of well-based permeable reactive barrier system for groundwater remediation, this site-scale study was carried to identify the flowpaths and controlling factors of plume at a remediation site in Suwon City, Korea. A total of 22 monitoring wells were installed as a grid system in the $4m{\times}4m$ square area by 1-m interval. For the groundwater characterization, various tests were performed including water-level monitoring, water sampling & analysis, pumping and slug tests, and tracer tests. The aquifer appeared to be unconfined with hydraulic conductivities (K) ranging from $2.6{\times}10^{-4}cm/s$ to $9.5{\times}10^{-3}cm/s$. The average linear velocity of groundwater was estimated to be $2.94{\times}10^{-6}m/s$, and the longitudinal dispersivity of a conservative tracer to be $5.94{\times}10^{-7}m^2/s$. Groundwater plume moves preferentially through the high-K zones, and the relatively high ion concentrations along the low-K zones implying deterred groundwater flow. Consequently, the spatial variation of hydraulic conductivity caused by aquifer heterogeneity and anisotropy appears to be the most important factor to maximize the effect of plume treatment system for application of in-situ groundwater remediation techniques.

• 공업화학
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• 제4권1호
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• pp.64-74
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• 1993

국내 부존 함티탄자철광으로부터 염화티타늄($TiCl_4$)을 제조키 위해 함티탄자철광의 arc-smelting으로부터 얻어지는 titanium slag의 유동층 염소화 반응을 조사하였다. Titanium slag의 유동층 염소화반응에 적절한 반응조건은 반응 온도 $950^{\circ}C$, 반응시간 90분, 염소가스의 유속 3.0cm/sec, titanium slag에 대한 petroleum coke의 무게비 0.18, 그리고 titanium slag 및 petroleum coke의 입자의 평균직경은 각각 $44.6{\mu}m$, $67.9{\mu}m$였다. 위 조건하에서 titanium slug 중의 97.07%의 티타늄이 염소화 되었으며 제조된 염화티타늄($TiCl_4$)의 순도는 96.2%였다.

• Nuclear Engineering and Technology
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• 제37권6호
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• pp.595-604
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• 2005

A new instrument, an average BDFT (Birectional Flow Tube), was proposed to measure the flow rate in single and two phase flows. Its working principle is similar to that of the Pilot tube, wherein the dynamic pressure is measured. In an average BDFT, the pressure measured at the front of the flow tube is equal to the total pressure, while that measured at the rear tube is slightly less than the static pressure of the flow field due to the suction effect downstream. The proposed instrument was tested in air/water vertical and horizontal test sections with an inner diameter of 0.08m. The tests were performed primarily in single phase water and air flow conditions to obtain the amplification factor(k) of the flow tube in the vertical and horizontal test sections. Tests were also performed in air/water vertical two phase flow conditions in which the flow regimes were bubbly, slug, and churn turbulent flows. In order to calculate the phasic mass flow rates from the measured differential pressure, the Chexal drift-flux correlation and a momentum exchange factor between the two phases were introduced. The test results show that the proposed instrument with a combination of the measured void fraction, Chexal drift-flux correlation, and Bosio & Malnes' momentum exchange model could predict the phasic mass flow rates within a $15\%$ error. A new momentum exchange model was also proposed from the present data and its implementation provides a $5\%$ improvement to the measured mass flow rate when compared to that with the Bosio & Malnes' model.

• 동력기계공학회지
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• 제18권4호
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• pp.23-28
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• 2014

In order to increase the performance of conventional hot water floor heating system, the bubble jet loop heat pipe for the system was developed. This experiment was conducted under next conditions : Working fluid was R-134a, charging ratio was 50%. A temperature of hot water, room temperature and flow rate were $60^{\circ}C$, $15^{\circ}C$ and 0.5~1.5 kg/min, respectively. The experimental results, show that bubble jet loop heat pipe had a high effective thermal conductivity of $4714kW/m^{\circ}C$ and a sufficient heat flux of $73W/m^2$ to heat the floor to $35^{\circ}C$ in case of the 1.5 kg/min of flow rate. So the bubble jet loop heat pipe has a possibility for appling of the floor heating system. Additionally, the visualization of bubble jet loop heat pipe was performed to understand the operating principle. Bubbles made by the narrow gap between inner tube and outer tube of evaporating part generate pulsation at liquid surface of working fluid. The pulsation had slug flow and wavy flow. So working fluid circulates in the bubble jet loop heat pipe as two phase flow pattern. And large amount of heat is transferred by the latent heat from evaporating part to condensing part.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2014년도 춘계학술대회
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• pp.626-628
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• 2014

정보검색 시스템은 사용자가 검색하고자 하는 정보를 보다 정확하고 신속하게 전달하는 데 그 목적이 있다. 그러나 현재의 검색 시스템은 단순 구문 분석 방식으로 사용자가 원하는 정확한 정보를 제공하지 못하고 있다. 본 논문에서는 온톨로지 서버구축을 통한 정보검색 시스템을 제안한다. 제안하는 시스템은 시맨틱 웹 기반의 정보검색 기법을 이용하여 구조화된 문서뿐만 아니라 다양한 포맷의 데이터들의 처리를 극대화 시키고자 한다. 또한 상호 운용성 및 데이터 통합을 위해 RDF(Resource Description Framework) 방식의 문서저장을 지원하여 신속하고 정확한 정보검색이 가능하다. 이는 다양한 웹 브라우저를 지원하며 웹에서의 효율적인 데이터 검색 분야에 활용될 것이다.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.97-109
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• 2022

Multi-dimensional coupling analysis is a research hot spot in nuclear reactor thermal hydraulic study and both the full-scale system transient response and local key three-dimensional thermal hydraulic phenomenon could be obtained simultaneously, which can achieve the balance between efficiency and accuracy in the numerical simulation of nuclear reactor. A one-dimensional to three-dimensional (1D-3D) coupling platform for the nuclear reactor multi-dimensional analysis is developed by XJTU-NuTheL (Nuclear Thermal-hydraulic Laboratory at Xi'an Jiaotong University) based on the CFD code Fluent and system code RELAP5 through the Dynamic Link Library (DLL) technology and Fluent user-defined functions (UDF). In this paper, the International Standard Problem (ISP) No. 43 is selected as the benchmark and the rapid boron dilution transient in the nuclear reactor is studied with the coupling code. The code validation is conducted first and the numerical simulation results show good agreement with the experimental data. The three-dimensional flow and temperature fields in the downcomer are analyzed in detail during the transient scenarios. The strong reverse flow is observed beneath the inlet cold leg, causing the de-borated water slug to mainly diffuse in the circumferential direction. The deviations between the experimental data and the transients predicted by the coupling code are also discussed.

• 한국발생생물학회지:발생과생식
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• 제25권2호
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• pp.93-104
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• 2021

Cutaneous melanoma is a fatal disease for patients with distant metastasis. Metformin is the most widely used anti-diabetic drug, and proved to suppress cell proliferation and metastasis in diverse cancers including melanoma. We previously reported that MEK inhibitor trametinib increases the expression of epithelial-mesenchymal transition (EMT) regulators and melanoma cell motility, which are suppressed by addition of metformin in A375 melanoma cells. To confirm our findings further, we first evaluated the effect of metformin in combination with another MEK inhibitor binimetinib on cell viability in G361 melanoma cells. We then investigated whether binimetinib affects the expression of EMT regulators and cell motility. We finally monitored the effect of metformin on binimetinib-induced cell migration. Cell viability assay showed that combination index (CI) value at ED₅₀ is 0.80, suggesting synergy for the combination of metformin with binimetinib. Our results also revealed that binimetinib increased the expression of EMT regulators such as integrin αV, fibronectin and slug, which correlate well with the enhanced cell migration in wound healing assay. Metformin, on the contrary, suppressed the expression of sparc, integrin αV, fibronectin and N-cadherin with the reduced cell motility. The combination treatment showed that metformin counteracts the binimetinib-induced increase of cell motility. Overall, these results suggest that metformin with binimetinib might be useful as a potential therapeutic adjuvant against cell survival and metastatic activity in melanoma patients.

• Molecules and Cells
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• 제45권12호
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• pp.935-949
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• 2022

Liver cancer has a high prevalence, with majority of the cases presenting as hepatocellular carcinoma (HCC). The prognosis of metastatic HCC has hardly improved over the past decade, highlighting the necessity for liver cancer research. Studies have reported the ability of the KiSS1 gene to inhibit the growth or metastasis of liver cancer, but contradictory research results are also emerging. We, therefore, sought to investigate the effects of KiSS1 on growth and migration in human HCC cells. HepG2 human HCC cells were infected with lentivirus particles containing KiSS1. The overexpression of KiSS1 resulted in an increased proliferation rate of HCC cells. Quantitative polymerase chain reaction and immunoblotting revealed increased Akt activity, and downregulation of the G1/S phase cell cycle inhibitors. A significant increase in tumor spheroid formation with upregulation of β-catenin and CD133 was also observed. KiSS1 overexpression promoted the migratory, invasive ability, and metastatic capacity of the hepatocarcinoma cell line, and these effects were associated with changes in the expressions of epithelial mesenchymal transition (EMT)- related genes such as E-cadherin, N-cadherin, and slug. KiSS1 overexpression also resulted in dramatically increased tumor growth in the xenograft mouse model, and upregulation of proliferating cell nuclear antigen (PCNA) and Ki-67 in the HCC tumors. Furthermore, KiSS1 increased the angiogenic capacity by upregulation of the vascular endothelial growth factor A (VEGF-A) and CD31. Based on these observations, we infer that KiSS1 not only induces HCC proliferation, but also increases the metastatic potential by increasing the migratory ability and angiogenic capacity.

• 한국응용곤충학회지
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• 제48권4호
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• pp.541-546
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• 2009

$24^{\circ}C$에서 작은뾰족민달팽이의 알 크기 (단경$\times$장경)는 $1.91{\times}2.19$ mm, 무게는 3.3 mg 이었다. 산란 직후의 알에서부터 발육하여 우화한 성체가 최초 산란 시까지 17주간의 무게는 발육일수가 경과할수록 증가하였으며, 온도별 무게는 $20^{\circ}C$에서 가장 무거웠으며, 다음은 24, 16 및 $28^{\circ}C$ 순이었다. 작은뾰족민달팽이가 산란한 난괴수의 부화율은 $20^{\circ}C$에서 95%로 가장 높았으며, 다음은 24, 16 및 $28^{\circ}C$의 순으로 유의한 차이가 있었다. 난괴당 알수는 $20^{\circ}C$에서 20개로 가장 많았으며 $28^{\circ}C$에서 10개로 가장 적었다. 누적 산란 일수는 $20^{\circ}C$에서 15일로 가장 길었으며, $24^{\circ}C$에서 9일로 가장 짧았고, 산란기간은 84~134일로 $16^{\circ}C$에서 가장 짧았으며, $20^{\circ}C$에서 가장 길었다. 그리하여 총 산란수는 $20^{\circ}C$에서 217개로 가장 많았고, $16^{\circ}C$에서 105개로 가장 적었다. 작은뾰족민달팽이의 알기간은 12~19일, 유체기간은 51~68일, 성체수명은 85~134일 이었으며, 알에서부터 성체수명까지의 총 생존기간은 $20^{\circ}C$에서 216일로 가장 길었으며, 다음은 $24^{\circ}C$에서 193일, $16^{\circ}C$에서 170일 및 $28^{\circ}C$에서 151일 순 이었다. 따라서 작은뾰족민달팽이의 산란, 발육 및 성체수명에 가장 유리한 온도는 $20^{\circ}C$로 여겨졌다.