• Journal of Satellite, Information and Communications
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• v.7 no.2
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• pp.25-29
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• 2012

In this paper, we implemented LED beam forming communication system controlled by stepping motor. ATMega1284 was used as a MCU of main control board which has two main external IO, one is RS232 for connection with PC, the other is PORT for connection with motor driving board. Stepping motor rotated 360 degree when provided 160 clock and its rotation radius was increased by Archimedian Spiral. So LED can provide its light anywhere in the space and its beam forming was controlled by PC connected with RS232 of main control board. The action of beam forming was verified via actual HW/SW implementation.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3714-3722
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• 2000

The research related to the mobility support in the Internet can he classified into two fields. One is Macro mobility and the other is Micro mobility In case of \lacro Mobility, the standard, RFC 2002 by IETF is getting focused. But for Micro mobility, a variety of strategies have been discussed. In this paper. we introduce the concept of an LA and propose the strategy that makes it possible for the LA to fully concern frequent local handoff without using the HA. Therefore we can limit the longest handoH delay to a certain degree regardless of the distance between the MN and the HA of the MN. For the registration cost and the packet drop probability due to the registration delay, we prove the performance enhancement of the existing Mobile IP in case that we apply the concept of the LA to existing Mobile IP.

• Archives of Metallurgy and Materials
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• v.64 no.3
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• pp.953-957
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• 2019

U-10wt.%Zr metallic fuel slugs containing rare-earth (RE: a rare-earth alloy comprising 53% Nd, 25% Ce, 16% Pr and 6% La) elements for a sodium-cooled fast reactor were fabricated by modified injection casting as an alternative method. The distribution, size and composition of the RE inclusions in the metallic fuel slugs were investigated according to the content of the RE inclusions. There were no observed casting defects, such as shrunk pipes, micro-shrinkage or hot tears formed during solidification, in the metallic fuel slugs fabricated by modified injection casting. Scanning electron micrographs and energy-dispersive X-ray spectroscopy (SEM-EDS) showed that the Zr and RE inclusions were uniformly distributed in the matrix and the composition of the RE inclusions was similar to that of a charged RE element. The content and the size of the RE inclusions increased slightly according to the charge content of the RE elements. RE inclusions in U-Zr alloys will have a positive effect on fuel performance due to their micro-size and high degree of distribution.

• International Journal of Molecular Medicine
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• v.43 no.6
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• pp.2319-2328
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• 2019

Exosomes serve important functions in cell-to-cell communication and biological functions by serving as a delivery cargo shuttle for various molecules. The application of an improved delivery method for microRNAs (miRNAs/miRs) may enhance their potential as a therapeutic tool in cardiac diseases. Thus, the present study investigated whether human peripheral blood-derived exosomes may be used as a delivery cargo system for miRNAs, and whether the delivery of miR-21 using a human peripheral blood derived-exosome may influence the degree of remodeling following myocardial infarction (MI). In H9C2 and HL-1 cells, miR-21 expression was successfully regulated by treatment with human peripheral blood derived-exosomes loaded with an miR-21 mimic or inhibitor compared with untreated cells. In addition, the mRNA and protein expression levels of SMAD family member 7 (Smad7), phosphatase and tensin homolog (PTEN) and matrix metalloproteinase 2 (MMP2), which are involved in cardiac fibrosis, were associated with the uptake of miR-21 mimic- or inhibitor-loaded exosomes. Similarly, the in vivo mRNA and protein expression of Smad7, PTEN and MMP2 were altered following treatment with miR-21 mimic- or inhibitor-loaded exosomes. Furthermore, miR-21 mimic-loaded exosomes enhanced fibrosis, whereas miR-21 inhibitor-loaded exosomes reduced fibrosis in a mouse MI model. These results suggested that miRNA-loaded human peripheral blood derived-exosomes may be used as a therapeutic tool for cardiac diseases.

• The Korean Journal of Mycology
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• v.4 no.1
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• pp.53-58
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• 1976

This study was undertaken to investigate the direct effect of three different kinds of steroid to Trichophyton(T.) mentagrophytes growth in vitro. A loopful of T. mentagrophytes was inoculated into Sabouraud's media and Sabouraud's media containing various concentrations of dexamethasone (0.04%-0.00004%) prednisolone (0.25%-0.00025%), triamcinolone acetonide (0.2%-0.0002%), Sabouraud's media containing imidazole nitrate (econasole nitrate) 10 micro gm. per cc. of media, and Sabouraud's media containing econazole nitrate $10{\mu}g$ per cc. of media of various dexamethasone concentrations (0.04%-0.00004%). After inoculation they were left for two weeks at room temparature and the colony diameter were compared between Sabouraud's media and Sabouraud's media containing various concentrations, of three different steroids, Sabouraud's media containing econazole nitrate and Sabouraud's media containing econazole nitrate of various dexamethasone concentrations. For complementary study, hanging slide culture were done between Sabouraud's media and Sabouraud's media containing various dexamethasone concentrations to compare the degree of branching of hyphae and sporulation serially. The study results were as follows: 1. There is no significant difference in growth rate of T. mentcgrophytes between Sabouraud's media and Sabouraud's media containing various concentrations of three different steroids. 2. There is no significant difference in growth rate of T. metagrophytes between Sabouraud's media containing econazole nitrate 10 micro gm per cc. of media and Sabouraud's media containing econazole nitrate 10 micro gm per cc. of media of various dexamethasone concentrations. 3. In hanging slide culture, there is no significant difference in branching of hyphae and sporulation between Sabouraud's media and Sabouraud's media containing various dexamethasone concentrations.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.107-112
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• 1990

The purpose of this study is to derive indirect values of volume of packed red cell(VPRC), without centrifugation, from erythrocyte sedimentation rate(ESR) of blood diluted with isotonic dextrose solution in cattle. Each of ten blood samples taken from apprently healthy Korean cows and Holstein cows was used to produce eight different mixture of autologous plasma and blood corpuscles such that their values of VPRC lay between 15 to 50ml/100ml, and then each of the blood mixture was again diluted with 5% dextrose solution. The measurements of ESR using 45 degree-angled capillary hematocrit tube, 1.1~1.2mm bore, ($45^{\circ}$-micro-ESR) were practised for the diluted blood of various levels of VPRC under the ambient temperature of $10^{\circ}$, $20^{\circ}$ and $30^{\circ}C$. Reliable values of VPRC on the basis of the correlating linear regressive equation to the ESR could be derived from the values of $45^{\circ}$-micro-ESR/hr in the mixture of one part of whole blood and one part of 5% dextrose solution(1:1). For an aid of practical use, authors suggested a list of the $45^{\circ}$-micro-ESR/hr values of the diluted blood equivalent to VPRC of whole blood.

• Journal of Life Science
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• v.22 no.6
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• pp.799-806
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• 2012

Approximately 80 species of bacteria were isolated from the fermented mushroom first and the HJ-57 antibacterial micro-organism was selected to the final isolation bacteria. It has a high degree of CMCase, amylase, and protease activity as well as high antibacterial activity against mushroom pathogenic bacteria without affecting the growth and development of Flammulina velutipes and Lentinus edodes mushrooms. The finally selected HJ-57 antibacterial micro-organism was identified as Bacillus sp. HJ-57. The initial pH for culture was pH7 and its optimum culture temperature was $35^{\circ}C$. The antibacterial material produced by Bacillus sp. HJ-57 showed a little antibacterial activity even in the 12 hr of culture, but showed the highest antibacterial activity in the 36~48 hr of culture. The HJ-57 antibacterial micro-organism also showed a high antibacterial activity against mushroom pathogenic bacteria and molds in the corn cob contained culture medium is used in Flammulina velutipes cultivators.

• The Journal of Engineering Geology
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• v.20 no.4
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• pp.461-465
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• 2010

Weathering and permeability in rocks play a very important role in underground disposal of radioactive waste and their long-term management as well as stability security of rock structures. Weathering and permeability of rocks are largely controlled by the characters of inner structures of rocks. In other words, weathering rate can be accelerated depending on the quantity of pore and microcrack in rocks. Quantitative evaluation of inner structures of rocks can serve as a tool that can assess the degree of weathering of rocks. Therefore it can be said that the understanding of three dimensional distribution of the inner structure of rocks is important for long-term management of rock structures. This study was performed to analyze three dimensional distribution of pore in rocks using Micro Focus X-ray CT on fresh granite and weathered granite from Korea. Results of the analysis clearly show distribution of pore and porosity of the inner rock.

• Advances in nano research
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• v.5 no.3
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• pp.245-251
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• 2017

Multiwalled carbon-nanotubes (MWCNT) and micro-structured carbon, such as biochar or activated carbon (AC), have been seen to significantly increase the growth indices of certain plant species such as maize (Zea mays L.). Seed imbibition is the stage where environmental factors that affect water transport across the seed coat barrier, make a large impact. This work explores the effect on water imbibition by maize seeds when the aqueous environment surrounding the seed is diluted by small concentrations (10 and 20 mg/l) of pristine MWCNT (p-MWCNT), carboxylate functionalized MWCNT (COO-MWCNT) and AC. The degree of sensitivity of the process to (i) large structural changes is seen by utilizing the nano (the MWCNT) and the micro (the AC) allotropic forms of carbon; (ii) to small changes in the purity and morphology of the p-MWCNT by utilizing 95% pure and 99% pure p-MWCNTs of slightly differing morphologies; and (iii) to MWCNT functionalization by using highly pure (97%) COO-MWCNT. Water imbibition was monitored over a 15 hour period by Near Infrared Thermography (NIRT) and also by seed weighing. Seed surface topography was seen by SEM imaging. Analysis of the NIRT images suggests rapid seed surface topological changes with the quantity of water imbibed. While further work is necessary to arrive at a conclusive answer, this work shows that the imbibition phase of the maize seed is sensitive to the presence of MWCNT even to small differences in the purity of the p-MWCNT and to small differences in the physicochemical properties of the medium caused by the hydrophilic COO-MWCNT.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7551-7554
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• 2013

Tumor-associated microRNAs have been detected in serum or plasma, but whether plasma microRNA-21 (miR-21) could be a potential circulating biomarker for gastric cancer (GC) prognosis in Chinese is still uncertain. Real-time quantitative reverse transcription PCR (qRT-PCR) was employed in this study to compare the relative expression of miR-21 between pre-operative and post-operative paired plasmas from 42 patients with primary GCs. The results showed that the expression levels of miR-21 in the post-operative plasmas were significantly reduced by an average of 18.2 times in all patients when compared to the pre-operative plasmas, and by 22.1 times in the subgroup of patients without family history, while only 1.76 times in the subgroup of patients with a family history. With respect of clinicopathological characteristics, the plasma miR-21 expression was highly associated with differentiation degree and lymph node metastasis rate. The results suggested plasma miR-21 could be a novel potential biomarker for GC prognosis and evaluation of surgery outcomes, especially in patients without a family history.