• Journal of Yeungnam Medical Science
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• v.30 no.1
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• pp.4-9
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• 2013

Leptin, a 16-kDa cytokine, is secreted by adipose tissue in response to the surplus of fat store. Thereby, the brain is informed about the body's energy status. In the hypothalamus, leptin triggers specific neuronal subpopulations (e.g., POMC and NPY neurons) and activates several intracellular signaling events, including the JAK/STAT, MAPK, PI3K, and mTOR pathway, which eventually translates into decreased food intake and increased energy expenditure. Leptin signal is inhibited by a feedback inhibitory pathway mediated by SOCS3. PTP1B involves another inhibitory pathway of leptin. Leptin potently promotes fat mass loss and body weight reduction in lean subjects. However, it is not widely used in the clinical field because of leptin resistance, which is a common feature of obesity characterized by hyperleptinemia and the failure of exogenous leptin administration to provide therapeutic benefit in rodents and humans. The potential mechanisms of leptin resistance include the following: 1) increases in circulating leptin-binding proteins, 2) reduced transport of leptin across the blood-brain barrier, 3) decreased leptin receptor-B (LRB), and/or 4) the provocation of processes that diminish cellular leptin signaling (inflammation, endoplasmic reticulum stress, feedback inhibition, etc.). Thus, interference of the cellular mechanisms that attenuate leptin signaling improves leptin action in cells and animal models, suggesting the potential utility of these processes as points of therapeutic intervention. Various experimental trials and compounds that improve leptin resistance are introduced in this paper.

• BMB Reports
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• v.34 no.4
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• pp.371-378
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• 2001

The Glycoprotein D (gD) gene of the HSV-1 strain F was cloned, sequenced, recombinated into the HcNPV (Hyphantria cunea nuclear polyhedrosis virus) expression vector and expressed in insect cells. The gD gene was located in the 6.43 kb BamHI fragment of the strainF. The open reading frame (ORF) of the gD gene was 1,185 by and codes 394 amino acid residues. Recombinant baculoviruses, GD-HcNPVs, expressing the gD protein were constructed. Spodoptera frugiperda cells, infected with the recombinant virus, synthesized a matured gX-gD fusion protein with an approximate molecular weight of 54 kDa and secreted the gD proteins into the culture media by an immunoprecipitation assay The fusion gD protein was localized on the membrane of the insect cells, seen by using an immunofluorescence assay The deduced amino acid sequence presents additional characteristics compatible with the structure of a viral glycoprotein: signal peptide, putative glycosylation sites and a long C-terminal transmembrane sequence. These results indicate the utility of the HcNPV-insect cell system for producing and characterizing eukaryotic proteins.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.411-419
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• 2016

This article investigates the problem of distributed channel selection in opportunistic spectrum access networks from a perspective of interference minimization. The traditional physical (PHY)-layer interference model is for information theoretic analysis. When practical multiple access mechanisms are considered, the recently developed binary medium access control (MAC)-layer interference model in the previous work is more useful, in which the experienced interference of a user is defined as the number of competing users. However, the binary model is not accurate in mathematics analysis with poor achievable performance. Therefore, we propose a real-valued one called stochastic MAC-layer interference model, where the utility of a player is defined as a function of the aggregate weight of the stochastic interference of competing neighbors. Then, the distributed channel selection problem in the stochastic MAC-layer interference model is formulated as a weighted stochastic MAC-layer interference minimization game and we proved that the game is an exact potential game which exists one pure strategy Nash equilibrium point at least. By using the proposed stochastic learning-automata based uncoupled algorithm with heterogeneous learning parameter (SLA-H), we can achieve suboptimal convergence averagely and this result can be verified in the simulation. Moreover, the simulated results also prove that the proposed stochastic model can achieve higher throughput performance and faster convergence behavior than the binary one.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.12
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• pp.1015-1020
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• 2016

An advantage of electric vehicles is that they are environmentally sustainable because they do not emit exhaust gases, such as $CO_2$ or Nox. A disadvantage is the low power performance of the motor and battery source, necessitating a reduction in the weight of the vehicle to increase efficiency. Another disadvantage is that the rechargeable battery enables an electric vehicle to only run for a limited number of miles before requiring electric charging. To solve these problems, the hybrid vehicle has been developed by combining environmental sustainability with the high performance of a conventional internal combustion engine. In this study, an electric UTV (Utility Terrain Vehicle) was transformed into a hybrid vehicle system by outfitting the vehicle with a drive auxiliary power system including a 125 cc internal combustion engine. This modification enabled us to extend the range of the hybrid UTV from 50km to 100km per one electric charging.

• Journal of ILASS-Korea
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• v.24 no.1
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• pp.21-26
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• 2019

In Korea, Medium-duty trucks are classified into GVW (Gross Vehicle Weight) 3.5~10tons. MDTs are mostly used for logistics or delivery between regions. There have been studied on diesel fuel vehicles for SUVs(Sports Utility Vehicle) or light-duty trucks. But MDTs have been not studied. Therefore, this study have been used MDTs for characteristic exhaust emission. Test was carried out using the certification test mode (NEDC, New European Driving cycle) and the NIER mode in chassis dynamometer of the MDTs. And emission gas was analyzed for PN (Particulate Number), PN size distribution and aldehydes, VOCs (Volatile Organic Compounds), PAHs (Polycyclic Aromatic Hydrocarbons). This paper concluded that EURO-IV trucks produced more MSATs than EURO V trucks. Depending on the engine temperature, more MSATs were generated in cold temperature than in the hot start operation. However, the driving speed, the opposite results was obtained.

• Clinics in Shoulder and Elbow
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• v.27 no.1
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• pp.117-125
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• 2024

While shoulder hemiarthroplasty is still used to treat young patients with shoulder pathology, the use of this procedure has substantially declined in recent years due to its significant complication profile. Glenoid wear with arthrosis is one of the major postoperative complications following shoulder hemiarthroplasty, and efforts to prevent this complication led many scientists to explore alternative weight-bearing surfaces on arthroplasty implants to decrease joint wear and improve patient outcomes. Pyrolytic carbon, or pyrocarbon, is a material that has better biocompatibility, survivorship, strength, and wear resistance compared to the materials used in traditional shoulder hemiarthroplasty. Pyrocarbon implants have been used in orthopedics for over 50 years; recently, their utility in shoulder hemiarthroplasty has garnered much interest. The purpose behind the use of pyrocarbon in shoulder hemiarthroplasty is to decrease the risk of progressive glenoid wear, especially in young active patients in whom joint preservation is important. Promising survivorship and outcomes have been demonstrated by recent studies, including limited glenoid wear following pyrocarbon hemiarthroplasty. Nevertheless, these clinical studies have been limited to relatively small case series with limited long-term follow-up. Accordingly, additional research and comparative studies need to be conducted in order to properly assess the therapeutic efficacy and value of pyrocarbon hemiarthroplasty.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.115-122
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• 2017

Recently, the on-board equipments of vessels are getting diversifications with high technologies. With changing the trends, the shipboard network is turning to the light-weight ethernet architecture for integrated data management. For that necessity, this paper covers a development of the gateway system which gathers and processes the measured analog or NMEA data from loaded equipments to convert the messages based on IEC 61162-450 (standard for light-weight ethernet network of ships) in engine parts of small vessel. To do this, we analyzed the requirements for standardization of ship's equipments and related studies. To solve the problems of existing equipments, we defined the additional data formats (sentence formatter), developed the gateway system, and verified the utility of the developed system. Consequently, we established an interfacing framework for management and application of the generated data based on the ethernet in vessel.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.325-331
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• 2018

We aimed to increase the utility of Broussonetia kazinoki (paper mulberry) by using its woody parts as a substrate for Lentinula edodes cultivation. Using different mixing ratios of paper mulberry and oak tree sawdust, five types of column-type media were prepared (1.2 kg each). Two L. edodes strains (NIFoS 2462 and NIFoS 2778) were used in this study. In the first flush, numerous small mushrooms were harvested because the fruited mushrooms were densely packed on the small media. The highest productivity was obtained with a 3:1 mixture of paper mulberry and oak tree sawdust (Q. acutissima:Q. mongolica, 1:1). In particular, for NIFoS 2462, the proportion of paper mulberry in the medium positively correlated with productivity. The size of NIFoS 2778 was uniform in all media tested. By contrast, the mushroom weight of NIFoS 2462 decreased, but the other characteristics were not significantly affected. Collectively, these findings suggest that B. kazinoki sawdust could be used to grow shiitake mushrooms and that some oak sawdust substitution is also possible. Our results could increase the utility of discarded by-products, such as sawdust.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.25-35
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• 2011

Traffic volume increases due to diversification of industry. Also, Automobile ownerships also increase steadily. It is estimated that the registered number of vehicle is expected to be 20 milion in the year 2015. These trends may result in increasing the number of woman drivers and elderly drivers. Therefore, this study aims to identify routes that reflect characteristics of each driver's preferences. A survey was conducted on different routes attributes for variances drivers. Driver types were classified by gender, age, and driving career. Accordingly, a weight for road composition attribute such as number of lanes, number of accidents, slope was estimated by using Swing Weighting technique in Multi-Attribute Utility Theory. In addition, a case study was conducted and identified weights were applied to routes. In result, drivers commonly prefer short route when they considered their routes. Also, male drivers prefer speedy and shorter route than that of female drivers. Elderly drivers prefer safe routes that represent low accidents rate. Moreover driving career under a year drivers prefer safe and easy routes. Therefore, we may conclude that the necessity of diversified route information is essential in the future car navigation system.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.164-169
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• 1998

In order to evaluate the utility of the bituminous coal fly ash, gypsum, oyster shell as soil amendments, acid sandy loam soil with low boron content were amended in the upper 15cm with amendments, and then chinese cabbage was cultivated in fall. Amendments treated were, in metric tons per hectare, i ) none(Check) ; ii) 80 fly ash(FA) ; iii) 4shell(SH) ; iv) 56 fly ash+24gypsum (FG) ; v) 40 fiy ash + 24 gypsum +0.8 shell(FGS). On the whole, amendments imoroved soil chemical properties and contents of N, P, K, Ca, and B in leaves. Among treatmens, FA prominently neutralized soil pH and increased available $P_2O_5$ ,B but decreased Fe contents in soils. FGS also affected the increment of exchangeable Ca, Mg, and available B. Yield response in fresh weight of chinese cabbage was in order of 85% for FGS>77% for FG>66% FA>5% for SH plants. Reducing sugar and vitamin-C contents of leaves depending on treatments showed the same tendencies as that in yields, whereas crude fiber opposite to theme. In particular, FA, FG, and FGS plants showed normal growth without boron deficiency symotoms which appeared in Check and SH plants.Taken together, FGS was an effective combination enable to maximize the utility of fly ash, gypsum, and shell as soil amemdments, especially in cabbage yield and quality.