• Biomolecules & Therapeutics
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• v.26 no.3
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• pp.290-297
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• 2018

We aimed to understand the molecular changes in host cells that accompany infection by the seasonal influenza A H1N1 virus because the initial response rapidly changes owing to the fact that the virus has a robust initial propagation phase. Human epithelial alveolar A549 cells were infected and total RNA was extracted at 30 min, 1 h, 2 h, 4 h, 8 h, 24 h, and 48 h post infection (h.p.i.). The differentially expressed host genes were clustered into two distinct sets of genes as the infection progressed over time. The patterns of expression were significantly different at the early stages of infection. One of the responses showed roles similar to those associated with the enrichment gene sets to known 'gp120 pathway in HIV.' This gene set contains genes known to play roles in preventing the progress of apoptosis, which infected cells undergo as a response to viral infection. The other gene set showed enrichment of 'Drug Metabolism Enzymes (DMEs).' The identification of two distinct gene sets indicates that the virus regulates the cell's mechanisms to create a favorable environment for its stable replication and protection of gene metabolites within 8 h.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.2
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• pp.103-107
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• 2000

Effect of aging treatment on the microstructures and mechanical properties of 7N01 Al alloy was investigated by differential scanning calorimetry, transmission electron microscopy, microhardness measurement and tensile test. Maximum hardness(125.7Hv) and tensile strength(447.3MPa) were obtained from the specimen aged at $120^{\circ}C$ for 32hrs. The major precipitation hardening phase was confirmed as coherent $MgZn_2({\eta}^{\prime})$ phase. Microhardness changes after peakaged condition showed very large decrease upon increased aging time. This result was attributed to the high transformation rate from coherent ${\eta}^{\prime}$ to incoherent ${\eta}$. It was found that the precipitation sequence of 7N01 Al alloy was GP zone${\rightarrow}$metastable spherical hcp $MgZn_2({\eta}^{\prime}){\rightarrow}$ equilibrium rodlike hcp $MgZn_2({\eta})$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4B
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• pp.365-371
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• 2002

In this paper, the fabricated power PHEMT devices for millimeter-wave that is below a gate-length of 0.2 $\mu\textrm{m}$ using electronic beam lithography technologies, and the DC and frequency characteristics and an output power characteristics were Measured at the various bias conditions. The unit process that is used in PHEMT's manufacture used that low-resistance ohmic contact, air-bridge and back-side lapping process technologies, and so on. The fabricated power PHEMT have an S521 gain of 4 dB and a maximum transconductance(gm) of 317 mS/mm, an unilateral current gain(fT) of 62 GHz, a maximum oscillation frequency(fmax) of 120 GHz at 35 GHz, and a maximum power output(Pmax) of 16 dBm, a power gain(GP) of 4 dB and a drain efficiency(DE) of 35.5 %.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.251-258
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• 1996

The V3 loop, a hypervariable domain of envelope glycoprotein, has an essential role in viral infectivity and has a major epitope for type-specific neutralizing antibody. In order to investigate genetic diversity of V3 region of gp120 of human immunodeficiency virus type 1 (HIV-1) isolated from Korean patients, DNA sequences encoding the C2 to V3 region were amplified by nested polymerase chain reaction (PCR) from uncultured peripheral blood mononuclear cells obtained from 15 HIV-1 seropositive patients and nucleotide sequences were determined. All nucleotide sequences from fifteen patients were compared with 8 distinctive subtypes (A-H) and another subtype O. Phylogenetic analysis was carried out with PHYLIP ver 3.5 (Dnapars) program. Of the 15 isolates, 14 HIV-1 subjects were clustered with subtype B, while one was clustered with subtype C. Intra-subtype B distance at the nucleotide and deduced amino acid level were maximum 17.7% and 37.0%, respectively. Intra-patient distance at the nucleotide and deduced amino acid level were maximum 7.3% and 17.8%, respectively. Analysis of the nucleotide sequences revealed that Korean types have relatively well conserved sequences. These findings could be useful for assessing the source of infection and developing an AIDS vaccine.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.114-120
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• 2010

The effects of grape seeds extract and grape peels extract prepared from grape pomace on the activity of antioxidant enzymes, degree of lipid peroxidation in serum and liver tissue were investigated in rabbits fed on high cholesterol diet. New Zealand white rabbits were divided as follows ; 1) NOR (normal group); 2) CHOL (cholesterol group); 3) GSH (cholesterol + grape seed extract group); 4) GPE (cholesterol + grape peel extract); 5) GSP (cholesterol + grape seed powder); 6) GPP (cholesterol + grape peel powder); 7) GE (cholesterol + grape seed and peel extract); 8) GP (cholesterol + grape seed and peel powder). Eight groups of rabbits were studied for 8 weeks. At the end of the experimental period, rabbits were sacrificed and the liver tissue were removed. Then, GSH, GPx, GST, CAT and MDA in the liver were measured. In liver tissues, total glutathione contents (GSH), glutathione peroxidase (GPx) and catalase (CAT) activity, which was significantly higher by grape seed extract supplementation. The level of malondialdehyde (MDA) was lower in the serum of rabbits fed grape seed extract or grape peel powder plus cholesterol than in the serum of rabbits fed cholesterol alone. It is therefore likely that grape seed extract prepared from grape pomace functioned as antioxidants in vivo, negating the effects of the oxidative stress induced by 1% cholesterol diet. The grape seed extract was found effective in converting the oxidized glutathione into reduced glutathione, and in removing $H_2O_2$ that is created by oxidative stress. The grape peel powder was found to have small influence on reduced glutathione content, CAT and GPX activity, but it increased GST activity in liver tissues, resulting in promoting the combination of lipid peroxide and glutathione (GSH), and further, lowering the formation of lipid peroxide in the serum. Therefore, grape pomace (grape seed extract and grape peel powder) supplementation is considered to activate the antioxidant enzyme system and prevent damage with hypercholesterolemia.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.213-213
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• 2017

High quality seed of proso millet that has high germination percentage, germination speed, and uniformity demanded to increases rates of mechanization in cereal crop cultivation. In order to improve germination characteristics, proso millet seeds were treated with red light, ultrasonication and liquid smoke (LS) solution that generated from hickory wood. All treatments were performed in seed priming solution with 100mM $NH_4NO_3$ at $15^{\circ}C$ for 24hrs under aeration condition. Seeds were exposed under light intensity of 2000 lux for 15m, 30m, 60m, and 120m in priming solution. Ultrasonic treatment was performed at 60%, 80%, and 100% intensity of 21.6 KHz for 5m, 10m, and 20m in priming solution. For LS treatment seed were soaked in 0%, 0.5%, 1.0%, 5.0% and 10.0% of diluted solution with $dH_2O$ or 100mM $NH_4NO_3$ solution. The effect of seed treatment was evaluated with germination percentage (GP), mean germination time (MGT), germination index (GI), germination rate (GR), Germination uniformity (GU) and heath seed percentage (HS). Our results demonstrate that red light (15min) or ultrasonication (21.6kHz, 5min) treatment improved MGT, GI, GR, and GU comparing to untreated control. Importantly, we show that LS treatments have significant effect on the health seedling and germination characteristics. Proso millet seeds that treated with 5% LS solution for 24hrs improves HS up to 97% that similar results obtained in 100mM $NH_4NO_3$ priming for 24hrs. The combined treatment with LS solution and 100mM $NH_4NO_3$ priming were not effective in all treatments. Our results demonstrate that treating seeds with LS or 100mM $NH_4NO_3$ priming or ultrasonication improves germination characteristics. The methods described here will help advance research using this species by increasing the germination performance at which successive seed pellet process.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.69-75
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• 1997

To evaluate in vitro anti-HIV efficacies of nucleoside derivatives, MT-4 cell line was infected with HIV-1 and HIV-2 respectively and treated with various compounds and the formerly approved drugs such as AZT, d4T, ddC and ddI. CPE method was used to evaluate their antiviral activity. Most dideoxynucleosides, AZT, d4T, ddC and ddI, showed anti-HIV activities against both viruses but no other compounds including anti-herpesvirus drugs did any. Further experiments were carried out to study their inhibitory mechanism of viral adsorption. The results showed no inhibition of syncytium formation due to an interaction between the gp120 expressed in HIV -infected cell surface and CD4 receptor on the uninfected cell surface in the presence of AZT. AZT showed no activity up to $100\;{\mu}g/ml$. Inhibition of reverse transcriptase (RT) in the presence of AZT-triphosphate was tested by using RT expressed in E. coli and purified and its $IC_{50}$ was 4.5 nM.

• Journal of the Korean Geophysical Society
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• v.9 no.2
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• pp.113-120
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• 2006

A lot of small-scale reservoirs that is extravagant in whole country are controlled state or real conditionthat correct data about the practice contents is not equipped all up to now. In this study, YungNam districts that region Gyeong-Ju city reservoir is distributed much of when flow speedily choose 23 peace among 73 small scale reservoir and experimented. Acquired data every 5 seconds, and user E/S and user value TS for orthocenter to 1 second interval and executes present ondition measurement using RTK-GPS. Could was wave and state that reservoir of 15 places (about 65%) gives protective care that do 3D modelling with acquired data, and now correct contents about reservoir state past through comparative analysis with data. Also, area of full water and wave that analyze effective storage and area of full water of 23 places reservoir could know that 20.63%, effective storage decreased as 3.34%. I wish to contribute about analysis about present reservoir state through this and method the adminstration direction.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.3
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• pp.31-37
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• 2015

In this paper, newly proposed dual-band microstrip antennas using stacked inverted-L-shaped parasitic elements are presented for GPS $L_1(1.575GHz)$ and $L_2(1.227GHz)$ bands. For making dual band which has large interval, ${\lambda}/4$($L_1$ band) inverted-L-shaped parasitic elements were stacked at both side of radiation apertures on the half-wavelength($L_2$ band) patch antennas. The resonance in the parasitic elements occurs through coupling to the patch. Next, due to using circular polarization at GPS, ${\lambda}/4$($L_1$ band) inverted-L-shaped parasitic elements was stacked using sequential rotation technique on the patch and both side of the diagonal corners of the antenna were eliminated to make dual-band circular polarization. The designed circular polarized antenna's dimensions are $0.43{\lambda}L{\times}0.43{\lambda}L{\times}0.06{\lambda}L$ (${\lambda}L$ is the free-space wavelength at 1.227 GHz). Measured -10 dB bandwidths was 120 MHz(7.6%) and 82.5 MHz(6.7%) at GPS $L_1$ and $L_2$ bands. and 3 dB axial ration bandwidths are 172 MHz(10.9%) and 25 MHz(2.03%), respectively. All of these cover the respective required system bandwidths. Within each of the designed bands, broadside radiation patterns were observed.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.697-702
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• 2023

Recently, with the introduction of drones, a core technology of the 4th industrial revolution, various convergence education using drones is being conducted in school education sites. In particular, drone theory and practice education is being conducted in connection with free semester classes and career exploration. The drone convergence education program has higher learner satisfaction than simple demonstration and practice education, and the learning effect is high due to direct practical experience. However, since practical education is being conducted for a large number of learners, it is impossible to restrict and control the flight of a large number of drones in a limited place. In this paper, we propose a monitoring system that allows the instructor to monitor multiple drones in real time and learners to recognize collisions between drones in advance when multiple drones are operated, focusing on education operated in schools. The communication module used in the experiment was equipped with GPS in Murata LoRa, and the server and client were configured to enable monitoring based on the location data received in real time. The performance of the proposed system was evaluated in an open space, and it was confirmed that the communication signal was good up to a distance of about 120m. In other words, it was confirmed that 25 educational drones can be controlled within a range of 240m and the instructor can monitor them.