• Journal of the Korean Society of Industry Convergence
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• v.15 no.2
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• pp.43-47
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• 2012

In this study, the experiments for surface enhancement of silver mirror substrate were done, where we checked the characteristics of silver mirror substrate made by Tollen's method. The surface enhancement of Bromothymol blue was analyzed by three kind of silver mirror substrates. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. Finally, we deduced that the adsorption orientation of bromothymol blue was little tilted flat to the silver mirror surfaces by using of the surface selection rules.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.1
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• pp.23-27
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• 2011

In this study, the experiments for surface enhancement of silver mirror substrates were done, where we checked the characteristics of silver mirror substrate made by Tollen's method. The surface enhancement of Eriochrome Black T(EBT) was analyzed by silver mirror substrates. We observed the SERS spectra of EBT. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. Finally, we deduced that the adsorption orientation of EBT was little tilted perpendicular to the silver mirror surfaces by using of the surface selection rules.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3707-3711
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• 2011

Silver nanoparticles coated with silica can be obtained by the reduction of $AgNO_3$ with hydrazine in the presence of NaOH-stabilized, active silicic acid (polysilicic acid). The size of the silver nanoparticles and the silica shell thicknesses were affected by varying the hydrazine content, the active silicic acid content and the experimental method (e.g. hydrothermal method). Typically, silver nanoparticles sized around 40 nm were aggregated, connected by silica. The presence of peaks centered around 400 nm in UV-vis spectra corresponds to the surface plasmon resonance of silver nanoparticles. The size of the aggregated silver nanoparticles increased with increasing hydrazine concentration. Under hydrothermal conditions at $150^{\circ}C$ the formation of individual silica particles was observed and the sizes of the silver nanoparticles were reduced. The hydrothermal treatment of silver nanoparticles at $180^{\circ}C$ gives a well-defined Ag@$SiO_2$ core-shell in aggregated silica sol particles. The absorption band observed at around 412 nm were red-shifted with respect to the uncoated silver nanoparticles (${\lambda}_{max}$ = 399 nm) due to the larger refractive index of silica compared to that of water. The formation of silver nanoparticles coated with silica is confirmed by UV-visible absorption spectra, transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) data.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.705-715
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• 2003

Procedures for treatment of molar furcation invasion defects range from open flap debridement, apically repositioned flap surgery, hemisection, tunneling or extraction, to regenerative therapies using bone grafting or guided tissue regenerative therapy, or a combination of both. Several clinical evaluations using regenerative techniques have reported the potential for osseous repair of treated furcation invasions. Regenerative treatment of maxillary molars are more difficult due to the multiple root anatomy and multiple furcation entrances therefore, purpose of this study was to evaluated histologically compomer and Ketac Silver as a barrier in the treatment of a bi-furcated maxillary premolar. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiostcal flap was elevated. Following decortication with 1/2 high speed round bur, furcation defect was made on maxillary premolar. 2 month later one premolar was filled with compomer and the other premolar was filled with Ketac Silver. After 4, 8 weeks, the animals were sacrificed by vascular perfusion. Tissue block was excised including the tooth and prepared for light microscope with H-E staining. Results were as follows. 1. Compomer & Ketac Silver restoration were encapsulated fine connective tissue. 2. In 4 weeks, compomer & Ketac Silver restoration slightly infiltrated inflammatory cells but not disturb the new bone or new cementum formation. 3. In 8 weeks, compomer & Ketac Silver restoration were less infiltrated iflammatory cell and encapsulated fine connective tissue. 4. Therefore, compomer & Ketac Silver filling to the grade III maxillary furcations with multiple root anatomy and multiple furcation entrances is possible clinical method and this technique is useful method for maxillary furcation involvement but it is thought that periodic maintenance should be needed

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.1-16
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• 1990

This study was to evaluate the cytotoxic effect in vitro and the tissue response within the rat peritoneal cavity to high copper amalgam and glass ionomer-silver cement, suggested for use as a retrograde endodontic filling material. In the cytotoxicity experiment, the radioactively ($^{51}Cr$) labeled L929 mouse fibroblasts were employed to determine the relative cytotoxicity of two experimental materials. Those materials were evaluated immediately after set and after one and seven days setting. In the tissue response experiment, two experimental materials were to evaluate mean peritoneal cellular count, differential cell count and the content of silver and copper in pooled packed cells and eluate samples taken by peritoneal lavage technique, and compared with surgical control after one day. two, four and six weeks of implantation. The results were as following: 1. High copper amalgam exhibited significant cytotoxicity immediately after set but showed no sign of toxicity after one day and seven days setting materials. 2. Glass ionomer-silver cement showed no sign of toxicity immediately after set and after one day and seven days setting. 3. High copper amalgam and glass ionomer-silver cement groups produce no significant difference in the mean peritoneal cell count when compared with the surgical control group after one day, two and four weeks of implantation. Surgical control group exhibited significantly a greater cell count when compared with the High copper amalgam group after six weeks. 4. High copper amalgam group increased significantly in the percentage macrophages after four and six weeks of implantation when compared with surgical control group. 5. The trace metal analysis involved an increased silver content in the elutes and an increased copper content in the packed cells of high copper amalgam group, and an increased silver content in the packed cells and elutes of glass ionomer-silver cement group.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.277-282
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• 2013

Purpose: This study was performed to evaluate the effectiveness of self-home dressing with nanocrystalline silver dressing method on the treatment of chronic ulcer wounds of the foot. Material and Methods: One hundred-nine patients with chronic foot ulcer due to various causes were treated with nanocrystalline silver dressing material. Dressing was done by themselves in their home. Dressing changes were performed every 2 to 3 days until complete reepithelization. Results: One hundred two cases of all cases had a complete reepithelization. It took 49 days to have a complete reepithelization on average. Seven cases failed to complete reepithelization because of infection. There was no silver intoxication in any cases. Conclusion: Using nanocrystalline silver is a useful dressing method for various superficial chronic ulcer and it can be done by themselves at their home. Thus it is considered to be more comfortable to both patients and doctors.

• Toxicological Research
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• v.30 no.3
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• pp.169-178
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• 2014

This review covers general information regarding the green synthesis of antibacterial silver nanoparticles. Owing to their antibacterial properties, silver nanoparticles are widely used in many areas, especially biomedical applications. In green synthesis practices, the chemical reducing agents are eliminated, and biological entities are utilized to convert silver ions to silver nanoparticles. Among the various biological entities, natural plant extracts have emerged as green reducing agents, providing eco-friendly routes for the preparation of silver nanomaterials. The most obvious merits of green synthesis are the increased biocompatibility of the resulting silver nanoparticles and the ease with which the reaction can be carried out. This review summarizes some of the plant extracts that are used to produce antibacterial silver nanoparticles. Additionally, background information regarding the green synthesis and antibacterial activity of silver nanoparticles is provided. Finally, the toxicological aspects of silver nanoparticles are briefly mentioned.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.583-591
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• 2008

The principal objective of this study was to assess the demands of the development program of silver health care professionals for elderly individuals residing in the Northern Gyeonggi-do area. To this end, a survey was conducted to investigate college students and employees related with elderly individuals in the area regarding their recognition, interest, and involvement in the labor training program. In the case of college students, the health education they had received was only 1 to 2 hours, from a school lecture(35%). The content of health education they desired was exercise(34%) and stress management skills(28%). The sources of health information they received included mass media(77%) and the internet(12%), and they trusted the information they received from health professionals(45%), and the mass media(34%). In the case of health professionals who were working at silver care facilities, the sources of health information to which they had access were mass media(51%), internet(14%), reliable health professionals(56%), mass media(22%), and books related to health (18%). The principal issues they reported as being relevant to the elderly were dementia(39%), hypertension(14%), arthritis (11%), and they reported that the most important personnel for elderly in the future would be care managers(44%), and care helpers(21%). 88% of subjects believed that there was a need for a silver welfare integrated information system. 43% of subjects used the internet, 77% of them required in-service training programs for the welfare of the elderly. Via this developmental program of silver health care professionals, a variety of new job opportunities can be provided in the future, and a program related to the silver service industry must be established as soon as possible.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.696-699
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• 2009

In present work, the antimicrobial effect of silver-nanoparticles/celite (SN/C) and silver carbonate/celite (SC/C) composites on Escherichia coli (E. coli) by use of silver nanoparticles and silver carbonate has been studied. Characteristics of the SN/C and SC/C composites were identified by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). SN/C and SC/C composites showed antimicrobial activity and the minimum inhibitory concentration of E. coli were 0.541, 0.344 ppm and the complete sterilizing concentration for the test organism were 1.427, 1.623 ppm. From the results we identified that SN/C and SC/C composites have antimicrobial activity to E. coli.

• BMB Reports
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• v.41 no.3
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• pp.204-209
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• 2008

The cDNAs encoding glutathione peroxidase (GPx) were cloned and sequenced from the liver of three Chinese carps with different tolerance to hepatotoxic microcystins, phyto-planktivorous silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis), and herbivorous grass carp (Ctenopharyngodon idellus). Using genome walker method, a 750 bp 5'-flanking region of the silver carp GPx gene was obtained, and several potential regulatory elements were identified in the promoter region of the GPx gene. The silver carp GPx gene was widely expressed in all tissues examined. Despite phylogenetic analysis, assigning this newly described carp GPx to the group of mammalian GPx2, the carp GPx seems more similar to GPx1 from a physiological point of view. The constitutive expression pattern of the three carp liver GPx gene, shows a positive relationship with their tolerance to microcystins.