• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.1
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• pp.58-61
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• 2012

In our report a relatively simple process for fast nano-texturing of p-type(100) CZ- silicon surface using silver catalyzed wet chemical etching in aqueous hydrofluoric acid (HF) and hydrogen peroxide solution($H_2O_2$) at room temperature. The wafers were saw-damaged by NaOH(6 wt%) at $60^{\circ}C$ for 150s. To obtain a nano-structured black surface, a thin layer of silver with thickness of 1 - 10 nm was deposited on the surfaces by evaporation system. After this process the samples were etched in HF : $H_2O_2$ : $H_2O$ = 1:5:10 at room temperature for 80s - 220s. Due to the local catalytic of the Ag clusters, this treatment results in the nano-scale texturing on the surface. This resulted in average reflectance values less than 9% after the silver on the surface of the wafers were removed.

• Journal of Plant Biotechnology
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• v.39 no.3
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• pp.175-181
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• 2012

Drought and high salinity stresses often imposes adverse effects on crop yield. MYB transcription factors have been shown to be an important regulator in defense responses to these environmental stresses. In this study, we have cloned and characterized a soybean gene GmMYB184 (Glycine max MYB transcription factor 184). Deduced amino acid sequences of GmMYB184 show highest homology with that from Vitis vinifera legume plant (75%). Different expression patterns of GmMYB184 mRNA were observed subjected to drought, cold, high salinity stress and abscisic acid treatment, suggesting its role in the signaling events in the osmotic stress-related defense response. Subcellular localization studies demonstrated that the GFP-GmMYB184 fusion protein was localized in the nucleus. Using the yeast assay system, the C-terminal region of GmMYB184 was found to be essential for the transactivation activity. These results indicate that the GmMYB184 may play a role in abiotic stress tolerance in plant.

• Korean Journal of Acupuncture
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• v.25 no.3
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• pp.29-41
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• 2008

Objectives : The aim of this study is to examine the effects of SSP(silver-spike point) therapy, applied to acupuncture points, on the middle cerebral arteries blood flows of sample group(tention-type headache patients, n=12) and control group(non tension-type headache patients, n=12), and on the reduction of their headaches, when applied to acupuncture points. Methods : We stimulated 6 acupuncture points for headache with the SSP(three times a week for three weeks), and measured VAS(visual analogue scale) and the blood flow of the middle cerebral arteries with TCD(transcranial doppler ultrasonography). Results : The blood flow of the middle cerebral artery and VAS of the sample group and the control group were compared four times(initial, 1weeks, 2weeks, 3weeks) and significant differences in the measurements were found at 3 weeks(p<.05). The blood flow of the middle cerebral artery of the sample group was significantly increased, and VAS was significantly decreased in both groups. Conclusions : The silver-spike-point low-frequency electrical-stimulation treatment, applied to acupuncture points, can significantly increase the blood flow of the middle cerebral arteries in headache patients and can thus alleviate their headaches.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.9
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• pp.1463-1471
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• 2009

Silver ions or silver nanoparticles have multi-functional properties. The cotton fabrics for providing multi-functional properties were treated with a nanosilver powder, UV-absorbers, and dimethyloldi-hydroxyethyleneurea (DMDHEU) alone and mixed solution. The physical properties, UV protection, antibacterial, and deodorizing properties of treated cotton fabrics were evaluated. The results were as a follows. The UV protection of cotton fabrics were increased by the application of a nanosilver and Uv-absorbers mixture. The UV protection of treated fabrics were improved by nanosilver/DMDHEU/UV-absorbers mixed solution. The wrinkle recovery properties of fabrics treated with DMDHEU and nanosilver improved. The stiffness of fabrics are decreased by a nanosilver/DMDHEU/UV-absorbers mixed solution. The antibacterial properties of the fabrics treated with nanosilver/DMDHEU/UV-absorbers mixed solution is 99.99%. The functional properties of cotton fabrics are shown to be better with aanosilver/DMDHEU/UV-absorbers mixed than treated with nanosilver alone.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.104-105
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• 2007

In this study, characteristics of silver ink-jet printing were investigated under various substrate treatments such as substrate heating, hydrophobic coating, and ultraviolet(UV)/ozone soaking. Fluorocarbon(FC) film was spin-coated on the polyimide (PI) film substrate to obtain a hydrophobic surface. Although hydrophobicity of the FC film could reduce the diameter of the printed droplets, the singlet images printed on the FC film surface showed irregularities in the pattern size and the position of the printed droplet along with droplet merging phenomenon. The proposed UV/ozone soaking of the FC film improved the uniformity of the pattern size and the droplet position after printing and substrate heating was very effective way in preventing droplet merging. By heating of the substrate after UV/ozone soaking of the coated FC film, silver conductive lines of 78-116 ${\mu}m$ line were successfully printed at low substrate temperatures of $40^{\circ}C$.

• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.208-213
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• 2017

Flexible opto-electronic devices are developed on the insulating layer deposited stainless steel (STS) substrates. The silicon dioxide ($SiO_2$) material as the diffusion barrier of Fe and Cr atoms in addition to the electrical insulation between the electronic device and STS is processed using the plasma enhanced chemical vapor deposition method. Noble silver (Ag) films of approximately 100 nm thickness have been formed on $SiO_2$ deposited STS substrates by E-beam evaporation technique. The films then were annealed at $650^{\circ}C$ for 20 min using the rapid thermal annealing (RTA) technique. It was investigated the variation of the surface morphology due to the interaction between Ag films and $SiO_2$ layers after the RTA treatment. The results showed the movement of Si atoms in silver film from $SiO_2$. In addition, the structural investigation of Ag annealed at $650^{\circ}C$ indicated that the Ag film has the material property of p-type semiconductor and the bandgap of approximately 1 eV. Also, the films annealed at $650^{\circ}C$ showed reflection with sinusoidal oscillations due to optical interference of multiple reflections originated from films and substrate surfaces. Such changes can be attributed to both formation of $SiO_2$ on Ag film surface and agglomeration of silver film between particles due to annealing.

• Journal of Integrative Natural Science
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• v.12 no.2
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• pp.47-57
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• 2019

Staphylococcus epidermidis is well-known not only as an innocuous normal flora species commonly isolated from human skin, but also as an important bacterial species to keep skin healthy, because this species can protect the human skin from pathogenic microorganisms. However, S. epidermidis turns into a potential pathogen in damaged skin, because these bacteria can easily form a biofilm on the wound area and provide antimicrobial resistance to other microorganisms embedded in the biofilm. Thus, it is important to kill S. epidermidis in the early stage of wound treatment and block the formation of biofilms in advance. In the present study, hydrogel wound dressings were fabricated using polyvinyl alcohol/polyethylene glycol containing silver citrate nanorods, which have been proven to have strong antimicrobial activity, especially against S. epidermidis, and their wound-healing efficacy was investigated in vivo using a rat experiment.

• Journal of Species Research
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• v.11 no.4
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• pp.278-286
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• 2022

During a field survey of Korean marine ciliates, we collected Pleuronema marinum from a brackish water sample. It is characterized by the presence of a contractile vacuole in mid-body, rather than the subterminal/ terminal contractile vacuole as in other congeners. The cells were examined in vivo and based on protargol and 'wet' silver nitrate impregnation. In addition, the nuclear 18S rRNA gene was sequenced using a single cell. The Korean population morphologically and molecularly resembles a Chinese population of P. marinum. Historical review of the species concludes that 1) two or more species have been assigned into P. marinum, 2) the position of contractile vacuole (e.g., in mid-body) is a valid character state, and 3) P. marinum is probably a rare species. Here we provide a monographic treatment of P. marinum to clarify the issue and for further studies of relevant species. Considering there are about 40 nominal species and complex nomenclatural acts in the genus Pleuronema, further studies should provide descriptions based on protargol and 'wet' silver impregnation with marker gene(s).

• Journal of dental hygiene science
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• v.23 no.1
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• pp.60-67
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• 2023

Background: In our study, a silver diamine fluoride (SDF) compound for the treatment of dental caries was synthesized to characterize its remineralization activity upon direct application to deciduous teeth. This study aimed to use microscopic computed tomography (microCT) and nanoindentation to evaluate whether SDF composite application could effectively arrest dental caries in five exfoliated primary molars. Methods: Carious teeth were extracted and visually examined using quantitative photofluorescence devices (Qraycam and QraypenTM). After performing microCT, the SDF composite was applied to the teeth according to the manufacturer's instructions. The researchers exchanged and precipitated the irritant saliva once daily for 1 week. The teeth were sectioned longitudinally through the centers of the mesial and distal surfaces, embedded, polished, and measured using nanoindentation. Thereafter, microCT was repeated. Statistical analyses were performed using GraphPad Prism software. Results: Following SDF composite application, a remineralized layer was observed on microCT images, and the hardness increased when measured using nanoindentation. We found that demineralized enamel presented with an increased number of irregular crystals in the deep carious lesion group compared with those in the shallow carious lesion group, resulting in a rougher surface. Conclusion: The SDF composite may be used for remineralization of early caries and cessation of advanced caries in primary molars.

• Journal of Conservation Science
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• v.27 no.1
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• pp.1-11
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• 2011

For the silver artifacts in the Koryo Dynasty excavated from Neungnae-ri Ganghwa island, the metallographic section analysis and hardness and chemical analysis were conducted. After making samples in the similar ratio of the composition concentration, the changes of the microstructure were checked according to the working method and temperature. The results show that those silver artifacts are Au-Cu alloys with 2 to 6 % of Cu. From the results it is judged that Cu was artificially alloyed with them to keep the proper hardness and identified that they were gilded by the amalgamation process seeing that mercury was included at the guilt layer. Also the porous texture on the surface of them could be formed at over $400^{\circ}C$, therefore, it is assumed the hot working or heat treatment at over $400^{\circ}C$ were performed. In silver artifacts made by the relief and repousse, they have the similar composition analysis to other 7 artifacts but the hardness is lower than pure silver. Consequently from differences in the hardness, it can be inferred that the low hardness of silver artifacts is concerned with manufacturing techniques.