• Journal of Conservation Science
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• v.35 no.1
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• pp.1-10
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• 2019

This study provides a comprehensive evaluation of general characteristics of sized silk fabrics for the painting purpose. Two particular types of silk fabrics used for painting background were compared: a recreation of historical material and a mass produced material of present day. The sizing process made the surface characteristics of the silk fabrics more suitable for painting. The dyeing properties of the fabrics were related to the surface area of the fabrics, and had no significant effect on their mechanical properties. The antibacterial activity of the tannin-based natural dyestuffs were maintained after the sizing. The performance assessment by the KES-FB system showed that the fabrics are more prone to deteriorate after the sizing because the glue layer receives the most of the physical stresses.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.151-155
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• 2003

Using gel filtration chromatography, high molecular silk fibroin with high purity was obtained and silk flbroin microsphere particles (SFMP) could be simply made by spray dryer method. Also, some of the physicochemical properties of SFMP and morphology were investigated. The average molecular weight of pure silk fibroin protein dissolved in calcium chloride is about 61,500g/㏖ as measured by gel permeation chromatography. SFMP was spherical in shape, and particles, sized average of 2 ${\pm}$ 10 ${\mu}$, were observed by SEM and particle analyzer, respectively. Obtaining microspheres particles by spray dryer method accelerated the transition from the random coil to the $\beta$-sheet structure during spray dryer treatment. It was identified by the basic fourier transform infrared spectroscopy of SFMP. The swelling ratio of SFMP is majorly dependent on the pH of the solution, not on the occurred gelation. The characteristic structure, which might be applicable to immobilization of drugs is superior to other matrix materials for the use of biomaterials with skin affinity.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.7-13
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• 2017

In this study, changes in gene expression after administration of silk fibroin fragments ($size{\approx}30kDa$) were evaluated in MG63 cells using a cDNA microarray assay. In addition, the level of alkaline phosphatase (ALP) activity and cellular proliferation in the group administered moderately sized silk fibroin fragments ($size{\approx}30kDa$) (MSF) were compared to those in the group administered smaller silk fibroin fragments (size < 1 kDa) (SSF). The results of the cDNA microarray assay show increased expression of genes that are related to the cell cycle and inflammation. ALP, bone morphogenetic protein-7, bone morphogenetic protein receptor type IA, and runt-related transcription factor 2 exhibited significantly lower expression compared to control cells (fold ratio < 0.5). Relative ALP activity of the $100{\mu}g/mL$ MSF group was significantly lower than that of the SSF group (P < 0.05). Thus, the MSF group showed increased expression of genes associated with cellular proliferation and inflammation but decreased expression of genes associated with osteogenesis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.2
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• pp.103-111
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• 2011

Purpose: Choukroun's platelet-rich-fibrin (PRF) is composed of platelets, white blood cells and fibrin matrix. It does not induce enough bone formation by itself but it can improve bone formation with calcium. Silk fibroin does not cause inflammatory reactions because it is bio-compatible and degradable. The purpose of this study was to exam the bone formation when a combination of Choukroun's PRF and silk fibroin was used. Methods: In this study, cell reactions to silk powder with differing molecular weights was first tested to select the appropriate silk powder. Then we applied these bone graft materials on defects of skull and in a peri-implant bony defect model in New Zealand rabbits. The results between the experimental and control s (non-grafted) group were analyzed. Results: The small sized silk fibroin powder showed increased cellular proliferation for bone-regeneration. There was no statistically significant difference between the experimental group and the control group at 6 weeks, but more new bone formation was observed in the combination graft group at 12 weeks (P<0.05). And in the dental implant model, the combination bone graft group showed much improved torque test results, which was statistically significant. Histomorphometric analysis showed more regenerated cortical bone and a higher mean bone to implant in the experimental group. Both were statistically significant. Conclusion: The combination graft of Choukroun's platelet-rich-fibrin (PRF) and silk fibroin powder can successfully restore the bony defects in a skull defected model and a peri-implant bony defects model.

• Journal of Conservation Science
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• v.30 no.2
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• pp.219-234
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• 2014

Fabrics, natural dyed fabrics, papers, natural dyed papers and paints were examined effects of colors and mechanical properties for materials of museum collections under anoxic treatment. Anoxic conditions using nitrogen and argon were oxygen concentration 0.01%, temperature($20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$), 50% RH and exposure time 30 days. Examined fabrics were raw silk fabric, UV irradiated raw silk fabric, degummed silk fabric, UV irradiated degummed silk fabric, cotton fabric, and UV irradiated cotton fabric. Natural dyed silk and cotton fabrics were dyed with fresh indigo, indigo, safflower, gromwell, madder sappanwood, amur cork tree, turmeric, gardenia, barberry root, pagoda tree flower, cochineal, lac, alnus japonica, gallnut, chestnut shell, and combination(indigo and safflower, indigo and amur cork tree, indigo and pagoda tree flower, indigo and sappanwood). Papers were Korean papers(mulberry paper, mulberry(70%) and rice straw(30%) mixed paper), Japanese paper(gampi paper), cotton paper, refined linen paper, cotton, linen & manila mixed fibre furnish, copy paper, news print, and alum sized mulberry paper. Natural dyed papers were dyed with indigo, sappanwood, madder, safflower, gardenia, amur cork tree, and pagoda tree flower. Paints were painted on alum-sized papers and silk fabrics using glue and pigments(azurite, malachite, cinnabar, vermilion, orpiment, gamboge, red lead, haematite, iron oxide red, indigo(lake), lac, cochineal, safflower, madder root lake, celadonite, smalt, ultramarine blue, lapis lazuli, prussian blue, kaolin, lead white, oyster-shell white, and clam-shell white). The color differences(${\Delta}E^*$) of all examined materials were below 1.5 or lowered than control samples after anoxic treatment. The variations of tenacity of yarns of fabrics and natural dyed fabrics after anoxic treatment were within that of standard silk and cotton fabrics. Gases(nitrogen and argon) and temperatures of anoxic treatment did not also affected color differences and variations of tenacity of materials.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.23-27
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• 2012

Bletilla striata is an important herb that is used as a paste for texture processing, an ingredient in incense and an additive for preserving calligraphic works and paintings. This study evaluated Bletilla striata, which has been used to preserve and manage the textiles and paper. In particular, this study examined the viscosity of a paste made from Bletilla striata, as well as the mechanical characteristics and antibiotic properties of the fabrics treated with the herb. In terms of viscosity, Bletilla striata paste was less sticky than wheat flour paste, meaning that the former can be applied more evenly to sized fabrics. In addition, Bletilla striata paste has high transparence, ensuring little color difference between the fabrics treated and not treated with the paste. Regarding the mechanical characteristics of the fabrics processed using the KES-FB System, the sized fabrics treated with Bletilla striata paste showed a higher flexibility and recovery rate and than those treated with the wheat flour paste, indicating that the former paste can be more effective in making fabrics maintain their original form and shape. Finally, silk fabrics treated with Bletilla striata showed very high antibiosis. This suggests that the paste can be used to develop antibiotic substances that can preserve textiles.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.2
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• pp.211-216
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• 2023

It has been shown that external pancreatic ductal stenting (EPDS) can reduce the incidence of clinically relevant postoperative pancreatic fistula. Although studies have described EPDS in open pancreaticoduodenectomy (PD), EPDS in minimally invasive PD has not been reported yet. Thus, the objective of this study was to describe the technique of EPDS in minimally invasive PD. The procedure was performed either laparoscopically or using a robot. Once PD was completed, key steps included triple enterotomy, threading of silk-suture through all enterotomies and exteriorization, completing posterior layer of pancreaticojejunostomy (PJ), railroading stent through preplaced silk-suture, intubation of stent into the pancreatic duct, completion of PJ, followed by hepaticojejunostomy and parietalization of jejunum at the stent exit site. EPDS in PD through a minimally invasive approach can be performed safely in selected cases with either a small-sized pancreatic duct or a soft pancreas.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.539-546
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• 2014

PURPOSE. Silk fibroin (SF) is a new degradable barrier membrane for guided bone regeneration (GBR) that can reduce the risk of pathogen transmission and the high costs associated with the use of collagen membranes. This study compared the efficacy of SF membranes on GBR with collagen membranes (Bio-$Gide^{(R)}$) using a rat calvarial defect model. MATERIALS AND METHODS. Thirty-six male Sprague Dawley rats with two 5 mm-sized circular defects in the calvarial bone were prepared (n=72). The study groups were divided into a control group (no membrane) and two experimental groups (SF membrane and Bio-$Gide^{(R)}$). Each group of 24 samples was subdivided at 2, 4, and 8 weeks after implantation. New bone formation was evaluated using microcomputerized tomography and histological examination. RESULTS. Bone regeneration was observed in the SF and Bio-$Gide^{(R)}$-treated groups to a greater extent than in the control group (mean volume of new bone was $5.49{\pm}1.48mm^3$ at 8 weeks). There were different patterns of bone regeneration between the SF membrane and the Bio-$Gide^{(R)}$ samples. However, the absolute volume of new bone in the SF membrane-treated group was not significantly different from that in the collagen membrane-treated group at 8 weeks ($8.75{\pm}0.80$ vs. $8.47{\pm}0.75mm^3$, respectively, P=.592). CONCLUSION. SF membranes successfully enhanced comparable volumes of bone regeneration in calvarial bone defects compared with collagen membranes. Considering the lower cost and lesser risk of infectious transmission from animal tissue, SF membranes are a viable alternative to collagen membranes for GBR.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.503-510
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• 2004

The study is one of fundamental researches for the development of future smart clothing and textile products with blocking properties from electromagnetic waves by analyzing human physical symptoms in using electromagnetic products in such an environments. Among various textiles in the experiment, nano silver has shown the best blocking performance from electromagnetic waves, which decreases depending on the distance. The power spectrum distribution and the incidence of electroencephalogram between blocking materials and aural stimuli has shown that, ${\beta}$, wave appeared to be active in all channels except for $T_4$, whereas all waves appeared with processed materials and especially with nano silver silk(NSS), ${\alpha}$, ${\beta}$, ${\theta}$, ${\gamma}$ waves appeared active in all regions. As for the brain mapping of ${\alpha}$ wave according to time, there found a strong activity in $P_3$, $P_4$ of the parietal lobe, with all materials on all time regions. With silk nylon metal(SNM) and NSS, it appeared strong in $F_3$, $F_4$ as well. As for ${\beta}$, wave, the activity appeared strong in frontal lobe before 7min. 30sec, where it tends to diminish abruptly in 7min. 30sec. to 13min. 30sec. region. After 13min., it regained gradually. With NSS, it appeared strong in all areas except for the farthest $T_4$. The appearance of ${\nu}$ wave can be deduced as it can affect human body with its toxic property while the silver particles become nano-sized. Therefore, the study conducted with human participants requires a proper particle size of it which would not penetrate cellular tissues and a proper binder and binding treatment for it, to prevent the physical fatigues and the potential diseases. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• Journal of Industrial Convergence
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• v.21 no.9
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• pp.33-39
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• 2023

Nano-sized materials can be coated on various substrates, and since this material is transparent and conductive, it can be used as a transparent electrode for electronic devices or an electrode for power supply. In this study, CNT and Ag nanowires were repeatedly coated using the silk screen technique, and samples formed up to 5 times were fabricated, and their optical and electrical properties were measured and analyzed. It was confirmed that marks were formed on the surface of the silkscreen-coated sample according to the coating direction, and the trend of transmittance and surface resistance according to the number of times of coating was investigated. As the number of coatings increased, transmittance and surface resistance tended to decrease. In particular, in the case of transmittance, the range of change was large in the samples coated 2 and 5 times. These changes were confirmed by the Ag nanowire coating. In addition, starting from 700 nm, the previous wavelength region increased according to the wavelength, while the above showed a tendency to decrease. The surface resistance was lowered from 9Ω/cm² when coating once to 0.856Ω/cm² when coating five times. It was found that the resistance value was affected by Ag similarly to the permeability. In the future, it is necessary to realize a desired transparent electrode through Ag concentration and coating of Ag nanowires with other methods and fusion with highly transparent CNT to apply to electronic devices.