• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.9
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• pp.1-6
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• 2009

We fabricated Gunn diodes with a double heat sink which has anode heat sink as well as cathode heat sink for efficient heat dissipation. We compared the DC characteristics of a double heat sink diode with a conventional cathode heat sink Gunn diode. It was shown that the Gunn diode with a single heat sink has the threshold voltage of 3 V, the peak current of 744 mA and the breakdown voltage of 4.8 V. Also, the Gunn diode with a double heat sink showed the threshold voltage of 2.5 V, the peak current of 778 mA and the breakdown voltage over 5 V.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7327-7331
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• 2014

Background: We had previously showed that the neutrophil lymphocyte ratio (NLR), ${\gamma}$-glutamyl transpeptidase (GGT) and carcinoembryonic antigen (CEA) are prognostic factors for metastatic colorectal cancer (mCRC) patients. In this study we developed a prognostic model based on these three indices. Materials and Methods: A total of 243 patients who were initially diagnosed as mCRC between 2005 and 2010 in the Sun Yat-sen University Cancer Center were studied. The endpoint was overall survival (OS). Results: NLR>3, elevated GGT and elevated CEA were confirmed as independent risk factors which could predict poor prognosis. Patients could be divided into three groups according to the number of risk factors they had. Those with two or three were defined as the high risk group, individuals with one risk factor as the modest risk group and patients without risk factor as the low risk group. The OS values for these three groups were 16.2 months (2.80~68.8), 24.2 months (4.07~79.0), and 37.2 months (12.6~87.8), respectively (p<0.001). Conclusions: We developed a simple but useful model based on NLR, GGT and CEA to provide prognostic information to clinical practice in highly selected mCRC patients. Further prospective and multi-center studies are warranted to test our model.

• Biomolecules & Therapeutics
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• v.24 no.1
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• pp.99-107
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• 2016

Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from $1{\mu}M$ to $50{\mu}M$ and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at $50{\mu}M$ induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.3
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• pp.15-20
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• 2015

After the US government declared 3D printing technology a next-generation manufacturing technology, there have been many practical studies conducted to expand 3D printing technology to manufacturing technologies, called AMERICA MAKES. In particular, the Keck Center, located at the University of Texas at El Paso, has studied techniques for easily combing the 3D stacking process with space mobility and expanded these techniques to simultaneous staking techniques for multiple materials. Additionally, it developed convergence manufacturing techniques, such as direct inking techniques, in order to produce a module structure that combines electronic circuits and components, such as CUBESET. However, in these studies, it is impossible to develop a unified system using traditional independent through simple sequencing connections. This is because there are many problems in the integration between the stacking modeling of 3D printers and post-machining, such as thermal deformations, the precision accuracy of 3D printers, and independently driven coordinate problems among process systems. Therefore, in this paper, the integration method is suggested, which combines these 3D printers and subsequent machining process systems through an Internet-based cloud. Additionally, the sequential integrated system of a 3D printer, an NC milling machine, machine vision, and direct inking are realized.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.7 s.98
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• pp.760-767
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• 2005

In this paper, we proposed a new type SIR bandpass filter using DAMLs. This filter is consisted of 2 layers with MEMS resonator layer and CPW feed line. DAMLs ring resonator is elevated with $10{\mu}m$ height from GaAs substrate. Using MEMS processing, we are able to realize SIR bandpass filter easily. Furthermore it is useful to integrate on conventional MMICs because it has CPW interfaces and ring resonator is isolated from substrate by air-gap. We optimized and measured the results that $S_{21}$ attenuation at rejected band is over 15 dB, insertion loss is inside the limit of 3 dB, and relative bandwidth is about $10\%$ at 60 GHz.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.2
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• pp.74-79
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• 2010

We have designed a millimeter-wave passive imaging sensor with multi-horn antenna array. Six horn array antenna is suggested that it is integrated into one housing, and this antenna is effectively configurated m space to assemble with LNA of WR-10 structure. Antenna is designed to have the peak gain of 17.5dBi at the center frequency of 94GHz, and the return loss of less than -25dB in W-band, and the small aperture size of $6mm{\times}9mm$ for antenna configuration with high resolution. LNA is designed to have total gain of more than 55dB and noise figure of less than 5dB for good sensitivity. We made a detector for DC output translation of millimeter-wave signal with zero bias Schottky diode. It is shown that good sensitivity of more than 500mV/mW.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.934-953
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• 2021

Ciglitazone is a member of the thiazolidinedione family, and specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. We hypothesized that ciglitazone as a PPARγ ligand in the absence of an adipocyte differentiation cocktail would increase adiponectin and adipogenic gene expression in bovine satellite cells (BSC). Muscle-derived BSCs were isolated from six, 18-month-old Yanbian Yellow Cattle. The BSC were cultured for 96 h in differentiation medium containing 5 µM ciglitazone (CL), 10 µM ciglitazone (CM), or 20 µM ciglitazone (CH). Control (CON) BSC were cultured only in a differentiation medium (containing 2% horse serum). The presence of myogenin, desmin, and paired box 7 (Pax7) proteins was confirmed in the BSC by immunofluorescence staining. The CL, CM, and CH treatments produced higher concentrations of triacylglycerol and lipid droplet accumulation in myotubes than those of the CON treatment. Ciglitazone treatments significantly increased the relative expression of PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, fatty acid synthase, stearoyl-CoA desaturase, and perilipin 2. Ciglitazone treatments increased gene expression of Pax3 and Pax7 and decreased expression of myogenic differentiation-1, myogenin, myogenic regulatory factor-5, and myogenin-4 (p < 0.01). Adiponectin concentration caused by ciglitazone treatments was significantly greater than CON (p < 0.01). RNA sequencing showed that 281 differentially expressed genes (DEGs) were found in the treatments of ciglitazone. DEGs gene ontology (GO) analysis showed that the top 10 GO enrichment significantly changed the biological processes such as protein trimerization, negative regulation of cell proliferation, adipocytes differentiation, and cellular response to external stimulus. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that DEGs were involved in the p53 signaling pathway, PPAR signaling pathway, biosynthesis of amino acids, tumor necrosis factor signaling pathway, non-alcoholic fatty liver disease, PI3K-Akt signaling pathway, and Wnt signaling pathway. These results indicate that ciglitazone acts as PPARγ agonist, effectively increases the adiponectin concentration and adipogenic gene expression, and stimulates the conversion of BSC to adipocyte-like cells in the absence of adipocyte differentiation cocktail.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.1-13
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• 2020

Tencent is an internet-based entertainment platform corporation using technology to enrich the lives of Tencent platform users and assist the contents expansion. Since 2000, Tencent have developed a great growth and innovation in entertainment contents domain. Tencent have become the market leading innovator due to the imitative innovation and M&A. The present study designed case study analyses to investigate the mechanism with regard to the growth strategy of Tencent corporation. Tencent began with imitative internet-based game and social messaging services but then added its own wechat messenger platform, now being extended to other products or services. This imitative innovation strategy enabled Tencent corporation to grow rapidly, to achieve outstanding growth. In addition, Tencent's M&A investment drive is underpinned by a vision of top management team and flexible organizational culture, from building out the Tencent's entertainment platform, game, finance, e-commerce, to global market expansion. While our results shed light on the implications to understanding Tencent's growth, there are limitations of the current study that should be considered when designing next research.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.471-472
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• 2006

The passivation technology is very important, because this technology can protect a device against the influence of ambient environment, and prevent the performance reduction. In this paper, we fabricated the $0.1{\mu}m\;{\Gamma}$-gate InAlAs/InGaAs metamorphic high electron mobility transistors (MHEMTs) on GaAs substrates using the low-k benzocyclobutene (BCB) and $Si_3N_4$ as a passivation and we performed the comparisons of characteristics of the MHEMTs. After passivation, the DC and RF measurement results were decreased either the conventional Si3N4 or BCB layers. The decrement of the BCB passivation was smaller than the $Si_3N_4$ passivation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.1
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• pp.47-53
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• 2022

In this study, the conditions for efficiently extracting polyphenols contained in black tea were optimized. In order to confirm the polyphenol content according to the degree of fermentation, the polyphenol content in black tea of the three fermentation degrees was compared. As the degree of fermentation increased, the polyphenol content increased, and it was confirmed that the theabrownin content, the largest in size, increased significantly. In addition, it was confirmed that the amount of theabrownin extraction increased by about 150% or more compared to other extraction water when extracting using mineral water, which was hard water. The antioxidant effects of black tea extract and the theabrownin was confirmed using ABTS assay. As a result, both extracts had antioxidant effects, and IC₅₀ values were confirmed to be 10.60 ppm and 13.21 ppm, respectively. And also, the anti-inflammatory effect of the theabrownin was confirmed that the mRNA expression of IL-8 increased by UVB irradiation was inhibited in a concentration dependent manner by the theabrownin. In addition, when theabrownin was treated with 10 ppm, the mitochondrial function decreased by UVB irradiation was restored to 86 ± 1.9% compared to the control group. Therefore, we concluded that theabrownin could protect mitochondrial damage caused by UVB irradiation.