• Title/Summary/Keyword: $U_3Si$

Search Result 499, Processing Time 0.031 seconds

Benzidine Induces Epithelial-Mesenchymal Transition of Human Bladder Cancer Cells through Activation of ERK5 Pathway

  • Sun, Xin;Zhang, Tao;Deng, Qifei;Zhou, Qirui;Sun, Xianchao;Li, Enlai;Yu, Dexin;Zhong, Caiyun
    • Molecules and Cells
    • /
    • v.41 no.3
    • /
    • pp.188-197
    • /
    • 2018
  • Benzidine, a known carcinogen, is closely associated with the development of bladder cancer (BC). Epithelial-mesenchymal transition (EMT) is a critical pathophysiological process in BC progression. The underlying molecular mechanisms of mitogen-activated protein kinase (MAPK) pathway, especially extracellular regulated protein kinases 5 (ERK5), in regulating benzidine-induced EMT remains unclarified. Hence, two human bladder cell lines, T24 and EJ, were utilized in our study. Briefly, cell migration was assessed by wound healing assay, and cell invasion was determined by Transwell assay. Quantitative PCR and western blot were utilized to determine both gene expressions as well as protein levels of EMT and MAPK, respectively. Small interfering RNA (siRNA) was transfected to further determine ERK5 function. As a result, the migration and invasion abilities were enhanced, epithelial marker expression was decreased while mesenchymal marker expression was increased in human BC cell lines. Meanwhile, benzidine administration led to activation of ERK5 and activator protein 1 (AP-1) proteins, without effective stimulation of the Jun N-terminal kinase (JNK) or p38 pathways. Moreover, Benzidine-induced EMT and ERK5 activation were completely suppressed by XMD8-92 and siRNAs specific to ERK5. Of note, ERK1/2 was activated in benzidine-treated T24 cells, while benzidine-induced EMT could not be reversed by U0126, an ERK1/2 inhibitor, as indicated by further study. Collectively, our findings revealed that ERK5-mediated EMT was critically involved in benzidine-correlated BC progression, indicating the therapeutic significance of ERK5 in benzidine-related BC.

열 화학기상증착법을 이용한 BCN 박막의 합성과 전기적 특성 분석

  • Jeon, Seung-Han;Song, U-Seok;Jeong, Dae-Seong;Cha, Myeong-Jun;Kim, Seong-Hwan;Kim, Yu-Seok;Lee, Su-Il;Park, Jong-Yun
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.388.2-388.2
    • /
    • 2014
  • 최근 그래핀 연구와 더불어 2차원 구조의 나노소재에 대한 관심이 급증하면서 육각형의 질화붕소(hexagonal boron nitride; h-BN) 박막(nanosheet) [1]이나 붕소 탄화질화물(boron caronitride; BCN) 박막 [2,3]와 같은 2차원 구조체에 대한 연구가 활발히 진행되고 있다. 그 중 BCN은 반금속(semimetal)인 흑연(graphite)과 절연체인 h-BN이 결합된 박막으로 원소의 구성 비율에 따라 전기적 특성을 제어할 수 있다는 장점이 있다. 따라서 다양한 나노소자로의 응용을 위한 연구가 활발히 진행되고 있다. 본 연구에서는 폴리스틸렌(polystyrene, PS)과 보레인 암모니아(borane ammonia)를 고체 소스로 이용하여 열화학기상증착법을 이용하여 BCN 박막를 SiO2 기판 위에 직접 합성하였다. SEM과 AFM 관측을 통해 합성된 BCN 박막을 확인하였으며, RMS roughness가 0.5~2.6 nm로 매우 낮은 것을 확인하였다. 합성과정에서 PS의 양을 조절하여 BCN 박막의 탄소의 밀도를 성공적으로 제어하였으며, 이에 따라 전기적인 특성이 제어되는 양상을 확인하였다. 또한 합성온도 변화에 따른 BCN 박막의 전기적인 특성이 제어되는 양상을 확인하였다. 추가적으로 같은 방법을 이용하여 BCN 박막을 Ni 위에서 합성하여 SiO2 기판위에 전사 하였다. 합성된 BCN 박막의 구조적 특징과 화학적 조성 및 결합 상태를 투과전자현미경(transmission electron microscopy), X-선 광전자 분광법(X-ray photoelectron spectroscopy)을 통해 조사하였다.

  • PDF

Identification of Vibrio species isolated from dark-banded rockfish (Sebastes inermis) (볼락(Sebastes inermis)에서 분리된 비브리오속 세균의 동정)

  • Nam, U-Hwa;Park, Jae-Rin;Pyo, Ji-Hye;Kim, Jeong-Ho
    • Journal of fish pathology
    • /
    • v.34 no.1
    • /
    • pp.105-110
    • /
    • 2021
  • We experienced mortality of dark-banded rockfish (Sebastes inermis) maintained in the rearing facility located in Gangneung, after transportation. Moribund fish showed various symptoms such as exophthalmia, skin ulcers, tail rots, gill rots, discoloration of liver with petechiae, yellowish fluid in intestines and ascites. Two different colonies were dominantly appeared after spreading the lesions on the agar plates and incubation. One isolate (SI_1) showed swarming movement on TSA, and formed yellow colonies on TCBS agar. The other (SI_2) showed no swarming motility and green colonies on TCBS agar. Both of them were Gram-negative. All of these results are similar with those of Genus Vibrio. They were identified as V. harveyi and V. gigantis by PCR with subsequent sequencing of 3 different genes (16 rDNA, recA, rpoA). V. harveyi is well-known as a serious pathogen of marine fish and invertebrates, while V. gigantis is known to be often isolated from marine invertebrates, but the pathogenicity is still unknown. We suspect V. harveyi as the cause of the mortality of dark-banded rockfish, but challenge experiments with these 2 Vibrio species are thought to be necessary to make a clear conclusion.

Effect of Post-Annealing and ZTO Thickness of ZTO/GZO Thin Film for Dye-Sensitized Solar Cell

  • Song, Sang-U;Lee, Gyeong-Ju;No, Ji-Hyeong;Park, On-Jeon;Kim, Hwan-Seon;Ji, Min-U;Mun, Byeong-Mu
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2013.02a
    • /
    • pp.405-406
    • /
    • 2013
  • Ga-doped ZnO (GZO)는 $300^{\circ}C$ 이상의 온도에서는 전기적으로 불안정하기 때문에 CIGS, CdTe, DSC와 같은 태양전지의 높은 공정온도 때문에 사용이 제한적이다. ZTO thin film은 Al2O3, SiO2, TiO2, ZnO tihin film과 비교하여 산소 및 수분에 대하여 투과성이 상대적으로 낮은 것으로 알려져 있다. 따라서 GZO single layer에 비하여 ZTO-GZO multi-layer를 구성하여 TCO를 제작하면, 높은 공정온도에서도 사용 가능하다. 실제 제작된 GZO single layer (300 nm)에서 비저항이 $7.69{\times}10^{-4}{\Omega}{\cdot}cm$에서 $500^{\circ}C$에서 열처리 후 $7.76{\times}10^{-2}{\Omega}{\cdot}cm$으로 급격하게 상승한다. ZTO single layer (420 nm)는 as-grown에서는 측정 불가했지만, $400^{\circ}C$에서 열처리 후 $3.52{\times}10^{-1}{\Omega}{\cdot}cm$ $500^{\circ}C$에서 열처리 후 $4.10{\times}10^{-1}{\Omega}{\cdot}cm$으로 열처리에 따른 큰 변화가 없다. 또한 ZTO-GZO multi-layer (720 nm)의 경우 비저항이 $2.11{\times}10^{-3}{\Omega}{\cdot}cm$에서 $500^{\circ}C$에서 열처리 후 $3.67{\times}10^{-3}{\Omega}{\cdot}cm$으로 GZO에 비하여 상대적으로 변화폭이 작다. 또한 ZTO의 두께에 따른 영향을 확인하기 위하여 ZTO를 2 scan, 4 scan, 6 scan 공정 진행 및 $500^{\circ}C$에서 열처리 후 ZTO, ZTO-GZO thin film의 비저항을 측정하였다. ZTO의 경우 $3.34{\times}10^{-1}{\Omega}{\cdot}cm$ (2 scan), $3.62{\times}10^{-1}{\Omega}{\cdot}cm$ (4 scan), $4.1{\times}10^{-1}{\Omega}{\cdot}cm$ (6 scan)으로 큰 차이가 없으며, ZTO-GZO에서도 $3.73{\times}10^{-3}{\Omega}{\cdot}cm$ (2 scan), $3.42{\times}10^{-3}{\Omega}{\cdot}cm$ (4 scan), $3.67{\times}10^{-3}{\Omega}{\cdot}cm$ (6 scan)으로 큰 차이가 없음을 확인하였다. 염료감응 태양전지에 적용하여 기존에 사용되는 FTO대신에 ZTO-GZO를 사용하며, 가격적 측면, 성능적 측면에서 개선 가능할 것으로 생각된다.

  • PDF

A Building Method of Security Architecture Framework on the Medical Information Network Environment (의료정보시스템상에서의 네트워크 보안기능 프레임워크와 보안 아키텍쳐 설계방법)

  • Lee, Dae-Sung;Noh, Si-Choon
    • Convergence Security Journal
    • /
    • v.11 no.4
    • /
    • pp.3-9
    • /
    • 2011
  • On health information network architecture, traffic along the path of traffic and security, blocking malicious code penetration is performed. The medical information system network security infrastructure study, which was whether to be designed based on the structure and methodology is designed to develop the security features. Health informati on system's functionality and capabilities framework for infrastructure is the backbone and structure. The design fea tures a framework for the overall network structure formation of the skeleton and forms the basic structure of the security methodology. Infrastructure capabilities to build the framework and the application functionality is being implemented. Differentiated in accordance with security zones to perform security functions and security mechanisms that operate through this study is to present. u-Healthcare future advent of cloud computing and a new health information environment, the medical information on the preparation of this study is expected to be utilized for security.

Uncertainty Evaluation of Color Measurement on Light Sources and Display Devices (광원 및 디스플레이 기기의 색특성 측정의 불확도 평가)

  • Park, Seong-Chong;Lee, Dong-Hoon;Kim, Yong-Wan;Park, Seung-Nam
    • Korean Journal of Optics and Photonics
    • /
    • v.20 no.2
    • /
    • pp.110-117
    • /
    • 2009
  • This work introduces the uncertainty evaluation formulation on color measurement of light sources and display devices, such as CIE 1931 (x, y) chromaticity, CIE 1960 (u, v) chromaticity, correlated color temperature, and distribution temperature. All the mentioned quantities are reduced from spectral data in the visible range, for which uncertainties are strongly correlated between different wavelengths. Using matrix algebra we have formulated the uncertainty propagation from the SI- traceable spectral irradiance standard to the individual color related measurement quantities taking the correlation between wavelengths into account. As a result, we have demonstrated uncertainty evaluation examples of 3 types of light sources: CIE illuminant A, LED white light, and LCD white light. This method can be applied to any other quantities based on spectral measurement such as solar irradiance, material color measurement, etc.

The individual-organizational suitability and individual-job suitability of front-line public officials Effect on Job Enthusiasm: Mediating Effect of Self-Efficacy (일선 공무원의 개인-조직적합성과 개인-직무적합성이 직무열의에 미치는 영향: 자기효능감의 매개효과)

  • Roh, Si Bum;Kim, Jong Rae
    • Journal of Digital Convergence
    • /
    • v.19 no.12
    • /
    • pp.79-89
    • /
    • 2021
  • The purpose of this study is to examine the effects of organizational/job suitability and self-efficacy on the job enthusiasm of public officials to enhance the government's organizational performance and goal achievement, and to examine what mediating effects of self-efficacy have. As the subject and method of the study, a survey was conducted with 248 civil servants from three cities (P, U, Y) in Gyeonggi-do, and structural equation analysis was used for the collected surveys. As a result of the study, organizational suitability of public officials had a positive effect on job enthusiasm, and self-efficacy was found to have a partial mediating effect on organizational suitability and job enthusiasm. In the case of job suitability, job enthusiasm was not significant, and self-efficacy had a fully mediated effect. Based on the results of this study, administrative and policy implications for enhancing the enthusiasm for the job of front-line civil servants of administrative organizations were presented.

Potential Antitumor ${\alpha}$-methylene-${\gamma}$-butyrolactone-bearing nucleic acid bases. 2. synthesis of $5^I-Methyl-5^I$-[2-(5-substituted uracil-1-yl)ethyl]-$2^I-oxo-3^I$-methylenetetrahydrofurans

  • Kim, Jack-C.;Kim, Ji-A;Park, Jin-Il;Kim, Si-Hwan;Kim, Seon-Hee;Choi, Soon-Kyu;Park, Won-Woo
    • Archives of Pharmacal Research
    • /
    • v.20 no.3
    • /
    • pp.253-258
    • /
    • 1997
  • Ten, heretofore unreported, $ 5^I-methyl-5^I-[2-(5-substituted uracil-1-yl)ethyl)]-2^I-oxo-3^I$-methylenetetrahydrofurans (H, F, Cl, Br, I, $ CH_3$,$CF_3$,$CH_2CH_3$,$ CH=CH2$, SePh) (7a-j) were synthesized and evaluated against four cell lines (K-562, FM-3A, P-388 and U-937). For the preparation of ${\alpha}$-methylene-${\gamma}$-butyrolactone-linked to 5-substituted uracils (7a-j), the convenient Reformasky type reaction was employed which involves the treatment of ethyl ${\alpha}$-(bromomethyl)acrylate and zinc with the respective 1-(5-substituted uracil-1-yl)-3-butanone (6a-j). The 5-substituted uracil ketones (6a-j) were directly obtained by the respective Michael type reaction of vinyl methyl ketone with the $K_2CO_3$(or NaH)-treated 5-substituted uracils (5a-j) in the presence of acetic acid in the DMF solvent. The .alpha.-methylene-.gamma.-butyrolactone compounds showing the most significant antitumor activity are 7e, 7f, 7h and 7j (inhibitory concentration $(IC_50)$ ranging from 0.69 to $2.9 {\mu}g/ml$), while 7b, 7g and 7i have shown moderate to significant activity. The compounds 7a, 7c and 7d were found to be inactive. The synthetic intermediate compounds 6a-j were also screened and found marginal to moderate activity where compounds 6b and 6g showed significant activity $(IC_50:0.4~2.8 {\mu}g/ml)$.

  • PDF

Controlling the Work Functions of Graphene by Functionalizing the Surface of $SiO_2$ Substrates with Self-assembled Monolayers

  • Jo, Ju-Mi;Kim, Yu-Seok;Cha, Myeong-Jun;Lee, Su-Il;Jeong, Sang-Hui;Song, U-Seok;Kim, Seong-Hwan;Jeon, Seung-Han;Park, Jong-Yun
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2012.08a
    • /
    • pp.400-401
    • /
    • 2012
  • 그래핀(Graphene)은 열 전도도가 높고 전자 이동도(200 000 cm2V-1s-1)가 우수한 전기적 특성을 가지고 있어 전계 효과 트랜지스터(Field effect transistor; FET), 유기 전자 소자(Organic electronic device)와 광전자 소자(Optoelectronic device) 같은 반도체 소자에 응용 가능하다. 그러나 에너지 밴드 갭이 없기 때문에 소자의 전기적 특성이 제한되는 단점이 있다. 최근에는 아크 방출(Arc discharge method), 화학적 기상 증착법(Chemical vapor deposition; CVD), 이온-조사법(Ion-irradiation) 등을 이용한 이종원자(Hetero atom)도핑과 화학적 처리를 이용한 기능화(Functionalization) 등의 방법으로 그래핀을 도핑 후 에너지 밴드 갭을 형성시키는 연구 결과들이 보고된 바 있다. 그러나 이러한 방법들은 표면이 균일하지 않고, 그래핀에 많은 결함들이 발생한다는 단점이 있다. 이러한 단점을 극복하기 위해 자가조립 단층막(Self-assembled monolayers; SAMs)을 이용하여 이산화규소(Silicon oxide; SiO2) 기판을 기능화한 후 그 위에 그래핀을 전사하면 그래핀의 일함수를 쉽게 조절하여 소자의 전기적 특성을 최적화할 수 있다. SAMs는 그래핀과 SiO2 사이에 부착된 매우 얇고 안정적인 층으로 사용된 물질의 특성에 따라 운반자 농도나 도핑 유형, 디락 점(Dirac point)으로부터의 페르미 에너지 준위(Fermi energy level)를 조절할 수 있다[1-3]. 본 연구에서는 SAMs한 기판을 이용하여 그래핀의 도핑 효과를 확인하였다. CVD를 이용하여 균일한 그래핀을 합성하였고, 기판을 3-Aminopropyltriethoxysilane (APTES)와 Borane-Ammonia(Borazane)을 이용하여 각각 아민 기(Amine group; -NH2)와 보론 나이트라이드(Boron Nitride; BN)로 기능화한 후, 그 위에 합성한 그래핀을 전사하였다. 기판 위에 NH2와 BN이 SAMs 형태로 존재하는 것을 접촉각 측정(Contact angle measurement)을 통해 확인하였고, 그 결과 NH2와 BN에 의해 그래핀에 도핑 효과가 나타난 것을 라만 분광법(Raman spectroscopy)과 X-선 광전자 분광법(X-ray photoelectron spectroscopy: XPS)을 이용하여 확인하였다. 본 연구 결과는 안정적이면서 패턴이 가능하기 때문에 그래핀을 기반으로 하는 반도체 소자에 적용 가능할 것이라 예상된다.

  • PDF

Trace element analysis of korean car windshield using LA-ICP-MS (LA-ICP-MS를 이용한 한국 자동차 유리의 미량원소 분석)

  • Min, Ji-Sook;Choi, Man-Sik;Heo, Sang-Cheol;Kim, Jae-Kyun
    • Analytical Science and Technology
    • /
    • v.22 no.3
    • /
    • pp.235-246
    • /
    • 2009
  • The analyses of minor and trace elements in glass debris were performed using LA-ICP-MS in order to identify manufacturers using real commercial samples. At first, a calibration curve was made using standard glass samples of NIST 610, 612, 614 and 616. $^{29}Si$ was used as an internal standard, and the ratios of metal/Si for each metal were compared with their concentrations. Based on elements in each sample and standard materials, 24 metals were quantified and the LOD in analysis, according to the blank sample, was in the range of 0.11 mg/kg (Ti)-4.91 mg/kg (Ca). Eleven samples from two manufacturers were collected and five sub-samples were taken from each sample for analysis. 15 elements (Co, Ce, Ca, Mn, Sr, Ba, Li, Rb, U, La, Th, Na, Al, Zr and Hf) were selected to identify manufacturers because some elements (Cu, Cr, Cd and Ni) were below the detection limit and some elements (Ti, Pr, Mg, Nb, Nd) were absent in the analysis of standards and others (Pb and Sn) had a problem of homogeneity. The attempts to identify manufacturers and the manufacturing period were performed through a triangular diagram. In the manufacturer discrimination by discriminant analysis, a canonical discriminant function was made based on Mn, Ce and Rb, and each sample could be identified.