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101.
Nu Ry Song Hee Yang Jiman Park Jung Yeon Kwon Nam Joo Kang Yong Seok Heo Ki Won Lee Hyong Joo Lee 《Food chemistry》2012
Cyanidin, an anthocyanidin found in fruits and vegetables, has been reported to possess anti-cancer effects. However, there is no study on the chemopreventive effect of cyanidin against neoplastic cell transformation and its molecular mechanisms. In the present study, we compare the anti-carcinogenic effects of cyanidin and cyanidin-3-glucoside (C3G) and investigate their underlying mechanisms. The inhibitory effect of cyanidin on EGF-induced cell transformation was higher than those of C3G in JB6 P+ mouse epidermal (JB6 P+) cells. Both cyanidin and C3G showed dose-dependent radical scavenging activities. It is indicated that the divergent inhibitory effects of cyanidin and C3G are not due to their antioxidant activities. We found that cyanidin, but not C3G, inhibited the EGF-induced Akt/p70S6K phosphorylation. Moreover, cyanidin directly suppressed the activity of PI3K by binding to PI3K directly in an ATP-competitive manner, which indicates that PI3K is one of the molecular targets of cyanidin. 相似文献
102.
Seung-Hong Lee Jung-In Choi Soo-Jin Heo Mi-Hwa Park Pyo-Jam Park Byong-Tae Jeon Se-Kwon Kim Ji-Sook Han You-Jin Jeon 《Food science and biotechnology》2012,21(1):239-246
Pancreatic β cells are very sensitive to oxidative stress and this may play an important role in β cell death in diabetes.
The protective effect of diphlorethohydroxycarmalol (DPHC), one of phlorotannin polyphenol compound purified from pae (Ishige okamurae) against high glucoseinduced oxidative stress was investigated using RINm5F pancreatic β cells. High glucose (30 mM) treatment
induced RINm5F pancreatic β cells cell death, but DPHC, at concentration 10 or 50 μg/mL, significantly inhibited the high
glucose-induced glucotoxicity and apoptosis. Furthermore, treatment with DPHC dose-dependently decreased thiobarbituric acid
reactive substances (TBARS), intracellular reactive oxygen species (ROS) generation and nitric oxide level increased by high
glucose. In addition, DPHC treatment increased activities of antioxidant enzymes including catalase (CAT), superoxide dismutase
(SOD), and glutathione peroxidase (GSH-px) in high glucose pretreated RINm5F pancreatic β cells. DPHC treatment improved the
secretory responsiveness following stimulation with glucose. These findings indicate that DPHC might be used as potential
nutraceutical agent which will protect the glucotoxicity caused by hyperglycemia-induced oxidative stress associated with
diabetes. 相似文献
103.
In order to obtain basic data for the utilisation of Zanthoxylum piperitum leaf as a functional substance in the food industry, the antioxidative and neuronal cell protective effects of silica-gel open column chromatographic fractions, obtained from Z. piperitum leaf, were examined. ABTS and FRAP assays indicated that the ZP4 fraction (eluted with methanol/chloroform, 1:4, v/v) of Z. piperitum leaf was a more potent radical-scavenger and reducing agent than the other five fractions. The ZP4 fraction also presented protective effects against H2O2-induced neurotoxicity in a dose-dependent manner. Therefore, our study verified that the ZP4 fraction has strong antioxidative and neuronal protective effects which are correlated with its high level of phenolics, particularly quercitrin, afzelin, and hyperoside. These phenolics of Z. piperitum leaf can be utilised as effective and safe functional food substances, i.e., natural antioxidants, and may reduce the risk of neurodegenerative disorders. 相似文献
104.
Pil Sun Heo 《Information Technology for Development》2019,25(3):424-454
ABSTRACTWhen assessing the structural role of an industry sector within an economic system, considering its relationship to other sectors is crucial. Among others, Information and Communication Technology (ICT) industry, one of the innovation accelerators or key engines of economic growth, is evaluated. Specifically, we analyze inter-industry production inducement linkages within a qualitative input–output analysis framework, since it is useful for understanding the key structure of an economic system. Our purpose is to understand the significant spillover structure of the Republic of Korea’s ICT industry within the national production system, as it has played an important role in the national economy and grown dramatically over the years. The findings from the structural analysis, focused on changes in links, are as follows: First, ICT manufacturing showed a higher degree of heterogeneity than ICT service sectors in its sensitivity effects structure, an indication that this sector needs to be utilized in various other industries. Second, the spectrum of industries having significant production inducement linkages with the ICT industry is limited and furthermore, the influence effects of the ICT manufacturing sector diminished considerably although the ICT industry’s sensitivity effects increased. Finally, intra-industry linkages within the ICT industry are gradually strengthened especially between ICT services and manufacturing. These findings call for sustained policy efforts to promote the virtuous circle in the overall inter-industry production inducement system, by increasing the utilization of products and services from other sectors by ICT sectors (especially ICT manufacturing) as well as the application of ICT in other sectors. 相似文献
105.
Mobility Engineering in Vertical Field Effect Transistors Based on Van der Waals Heterostructures 下载免费PDF全文
Yong Seon Shin Kiyoung Lee Young Rae Kim Hyangsook Lee I. Min Lee Won Tae Kang Boo Heung Lee Kunnyun Kim Jinseong Heo Seongjun Park Young Hee Lee Woo Jong Yu 《Advanced materials (Deerfield Beach, Fla.)》2018,30(9)
Vertical integration of 2D layered materials to form van der Waals heterostructures (vdWHs) offers new functional electronic and optoelectronic devices. However, the mobility in vertical carrier transport in vdWHs of vertical field‐effect transistor (VFET) is not yet investigated in spite of the importance of mobility for the successful application of VFETs in integrated circuits. Here, the mobility in VFET of vdWHs under different drain biases, gate biases, and metal work functions is first investigated and engineered. The traps in WSe2 are the main source of scattering, which influences the vertical mobility and three distinct transport mechanisms: Ohmic transport, trap‐limited transport, and space‐charge‐limited transport. The vertical mobility in VFET can be improved by suppressing the trap states by raising the Fermi level of WSe2. This is achieved by increasing the injected carrier density by applying a high drain voltage, or decreasing the Schottky barrier at the graphene/WSe2 and metal/WSe2 junctions by applying a gate bias and reducing the metal work function, respectively. Consequently, the mobility in Mn vdWH at +50 V gate voltage is about 76 times higher than the initial mobility of Au vdWH. This work enables further improvements in the VFET for successful application in integrated circuits. 相似文献
106.
Nanoparticle‐Enhanced Silver‐Nanowire Plasmonic Electrodes for High‐Performance Organic Optoelectronic Devices 下载免费PDF全文
Taehyo Kim Saewon Kang Jungwoo Heo Seungse Cho Jae Won Kim Ayoung Choe Bright Walker Ravi Shanker Hyunhyub Ko Jin Young Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Improved performance in plasmonic organic solar cells (OSCs) and organic light‐emitting diodes (OLEDs) via strong plasmon‐coupling effects generated by aligned silver nanowire (AgNW) transparent electrodes decorated with core–shell silver–silica nanoparticles (Ag@SiO2NPs) is demonstrated. NP‐enhanced plasmonic AgNW (Ag@SiO2NP–AgNW) electrodes enable substantially enhanced radiative emission and light absorption efficiency due to strong hybridized plasmon coupling between localized surface plasmons (LSPs) and propagating surface plasmon polaritons (SPPs) modes, which leads to improved device performance in organic optoelectronic devices (OODs). The discrete dipole approximation (DDA) calculation of the electric field verifies a strongly enhanced plasmon‐coupling effect caused by decorating core–shell Ag@SiO2NPs onto the AgNWs. Notably, an electroluminescence efficiency of 25.33 cd A?1 (at 3.2 V) and a power efficiency of 25.14 lm W?1 (3.0 V) in OLEDs, as well as a power conversion efficiency (PCE) value of 9.19% in OSCs are achieved using hybrid Ag@SiO2NP–AgNW films. These are the highest values reported to date for optoelectronic devices based on AgNW electrodes. This work provides a new design platform to fabricate high‐performance OODs, which can be further explored in various plasmonic and optoelectronic devices. 相似文献
107.
Jihun Kim Jun Sung Jang Seung Wook Shin Hyeonghun Park Woo-Lim Jeong Seung-Hyun Mun Jung-Hong Min Jiyoung Ma Jaeyeong Heo Dong Seon Lee Jung-Je Woo Jin Hyeok Kim Hyeong-Jin Kim 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2370156
Herein, a novel combination of Mg- and Ga-co-doped ZnO (MGZO)/Li-doped graphene oxide (LGO) transparent electrode (TE)/electron-transporting layer (ETL) has been applied for the first time in Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells (TFSCs). MGZO has a wide optical spectrum with high transmittance compared to that with conventional Al-doped ZnO (AZO), enabling additional photon harvesting, and has a low electrical resistance that increases electron collection rate. These excellent optoelectronic properties significantly improved the short-circuit current density and fill factor of the TFSCs. Additionally, the solution-processable alternative LGO ETL prevented plasma-induced damage to chemical bath deposited cadmium sulfide (CdS) buffer, thereby enabling the maintenance of high-quality junctions using a thin CdS buffer layer (≈30 nm). Interfacial engineering with LGO improved the Voc of the CZTSSe TFSCs from 466 to 502 mV. Furthermore, the tunable work function obtained through Li doping generated a more favorable band offset in CdS/LGO/MGZO interfaces, thereby, improving the electron collection. The MGZO/LGO TE/ETL combination achieved a power conversion efficiency of 10.67%, which is considerably higher than that of conventional AZO/intrinsic ZnO (8.33%). 相似文献
108.
Seungki Jo Seungjun Choo Fredrick Kim Seung Hwae Heo Jae Sung Son 《Advanced materials (Deerfield Beach, Fla.)》2019,31(20)
The growing concern over the depletion of hydrocarbon resources, and the adverse environmental effects associated with their use, has increased the demand for renewable energy sources. Thermoelectric (TE) power generation from waste heat has emerged as a renewable energy source that does not generate any pollutants. Recently, ink‐based processing for the preparation of TE materials has attracted tremendous attention because of the simplicity in design of power generators and the possibility of cost‐effective manufacturing. In this progress report, recent advances in the development of TE inks, processing techniques, and ink‐fabricated devices are reviewed. A summary of typical formulations of TE materials as inks is included, as well as a discussion on various ink‐based fabrication methods, with several examples of newly designed devices fabricated using these techniques. Finally, the prospects of this field with respect to the industrialization of TE power generation technology are presented. 相似文献
109.
Jong Heo David Lam George H. Sigel Jr. Edgar A. Mendoza David A. Hensley 《Journal of the American Ceramic Society》1992,75(2):277-281
Structural development of tellurite glasses with the addition of Li2 O and Na2 O has been studied using infrared, Raman, and X-ray photoelectron spectroscopies. The increase in intensity of the peak at 755 cm−1 in the infrared spectra as compared to the peak at 620 cm −1 suggests the transformation of TeO4 building units to TeO3 pyramids with the addition of alkali oxide. Proposed structural change is further supported by the strong compositional dependence of the 755-cm−1 peak in the Raman spectra as well as by the formation of a shoulder in the O 1 s peak of X-ray photoelectron spectra. In contrast to alkali silicate glasses, formation of nonbridging oxygens with the addition of alkali oxide is not observed. 相似文献
110.
Nonfullerene Electron Transporting Material Based on Naphthalene Diimide Small Molecule for Highly Stable Perovskite Solar Cells with Efficiency Exceeding 20% 下载免费PDF全文
Su‐Kyo Jung Jin Hyuck Heo Dae Woon Lee Seung‐Chul Lee Seung‐Heon Lee Woojin Yoon Hoseop Yun Sang Hyuk Im Jong H. Kim O‐Pil Kwon 《Advanced functional materials》2018,28(20)
This study reports a new nonfullerene electron transporting material (ETM) based on naphthalene diimide (NDI) small molecules for use in high‐performance perovskite solar cells (PSCs). These solar cells simultaneously achieve high power conversion efficiency (PCE) of over 20% and long‐term stability. New NDI‐ID (N,N′‐Bis(1‐indanyl)naphthalene‐1,4,5,8‐tetracarboxylic diimide) consisting of an N‐substituted indane group having simultaneous alicyclic and aromatic characteristics is synthesized by a low‐cost, one‐step reaction, and facile purification method. The partially flexible characteristics of an alicyclic cyclopentene group on indane groups open the possibility of low‐temperature solution processing. The conformational rigidity and aromaticity of phenyl and alicyclic groups contribute to high temporal stability by strong secondary bonds. NDI‐ID has herringbone packed semiconducting NDI cores that exhibit up to 0.2 cm2 V?1 s?1 electron mobility in field effect transistors. The inverted PSCs based on CH(NH2)2PbI3–xBrx with NDI‐ID ETM exhibit very high PCEs of up to 20.2%, which is better than that of widely used PCBM (phenyl‐C61‐butyric acid methyl ester) ETM‐based PSCs. Moreover, NDI‐ID‐based PSCs exhibit very high long‐term temporal stability, retaining 90% of the initial PCE after 500 h at 100 °C with 1 sun illumination without encapsulation. Therefore, NDI‐ID is a promising ETM for highly efficient, stable PSCs. 相似文献