• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.551-559
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• 2007

This study was to investigate if cervical vertebrae maturation stages are as useful as hand-wrist maturation stages in evaluating the mandibular growth. The subject consisted of 292 girls aged from 8 to 16 years with normal occlusion. They were classified according to diagnosis by using studycast, lateral cephalogram, and handwrist X-ray film. The results were as follow: 1. Cervical vertebrae and hand-wrist maturation stages increased with age. 2. All mandibular measurements (Ar-Go, Go-Me, N-Go, S-Gn, N-Me) increased linearly with cervical vertebrae maturation stages. 3. Ar-Go, Go-Me, N-Go, S-Gn increased linearly with hand-wrist maturation stages. 4. Ar-Go, Go-Me, N-Go, S-Gn increased relatively rapidly between cervical vertebrae maturation stages 3 and 4. Go-Me and S-Gn increased relatively rapidly between hand-wrist maturation stages 6 and 7. 5. Ar-Go, Go-Me, N-Go, S-Gn, N-Me had high correlations with cervical vertebrae maturation stages as well as hand-wrist maturation stages. These results suggest that cervical vertebrae maturation stages are reliable on evaluating the mandibular growth.

• Journal of the Korean Society of Costume
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• v.58 no.3
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• pp.105-115
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• 2008

A Go-go-kwan is a particular hat which has worn by married woman in Mongol and Yuan dynasty in China. It is also widely called as a Boktak in Mongol. The Go-go-kwan, recorded in jip-sa and in the miniature painting of 14th century is the early type of go-go-kwan. Later type can be seen from the relic collections of Gyeonggi Provincial Museum in Korea. The Go-go-kwan is composed with three parts ; feather part, tube part and hat part. Among the feathers, the largest one is as long as four times of the length of the tube and the shortest one is half the length of the tube. The tube is made of light weight wood such as white birch or bamboo, and covered with silk. Some of the hats were made exactly to fit on the head whereas others were designed to wear on the head as like jobawi.

• Membrane Journal
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• v.27 no.3
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• pp.255-262
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• 2017

In this study, systematic integration of graphene oxide (GO) into polyacrylonitrile (PAN) nanofibers was accomplished by electrospinning to examine their mechanical properties. Exfoliated GO was initially prepared by the modified Hummer's method, and the surface of the GO was modified with an organic surfactant (e.g., cetyltrimetylammonium chloride) to improve its stability and dispersity. The overall mechanical property of the nanofiber composite membranes was highly improved. Particularly, the composite membranes with the modified GO exhibited much improved mechanical property, presumably due to the increased stability and dispersity of GO during electrospinning.

• Journal of Environmental Science International
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• v.26 no.1
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• pp.1-10
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• 2017

In this study, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/graphene oxide (GO) nanocomposite films containing various content of GO were prepared using solution casting method. The effect of GO content on Young's modulus and dispersion of GO in PHBV matrix was investigated. Also, the thermomechanical properties, oxygen transmission rates and hydrolytic degradation of PHBV/GO nanocomposite films were studied. The addition of GO into PHBV improves the Young's modulus and decreases thermal expansion coefficient. The improvement can be mainly attributed to good dispersion of GO and interfacial interactions between PHBV and GO. Furthermore, PHBV/GO nanocomposite films show good oxygen barrier properties. PHBV/GO nanocomposites show lower hydrolytic degradation rates with increasing content of GO.

• Polymer(Korea)
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• v.38 no.4
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• pp.502-509
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• 2014

Carbon-based nanoplatelets such as graphene oxide (GO) sheets and graphite nanoplatelets (GNPs) are frequently used as conductive nanofillers for polymer nanocomposites. In this study, polystyrene (PS)/GO and PS/GNP nanocomposites were prepared through a latex technology and investigated to compare the effect of nanofillers on rheological and electrical properties of the PS nanocomposites. PS particles were prepared by emulsifier-free emulsion polymerization and GO was synthesized by using the modified Hummers' method from graphite. Hydrophilic GO was dispersed in aqueous PS suspension, but hydrophobic GNPs were dispersed with the help of a surfactant. In comparison with PS/GO nanocomposites, the rheological properties of PS/GNP counterparts were not too high because GNP existed in aggregates of graphene layers. Conducting pathways of PS/GO and PS/GNP nanocomposites were achieved at the electrical percolation threshold of 0.50 and 5.82 wt%, respectively. The reason for enhanced electrical conductivity in PS/GO nanocomposites is that GO was thermally reduced during molding.

• Journal of Nutrition and Health
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• v.39 no.1
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• pp.3-10
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• 2006

Effects of garlic powder supplementation on blood lipid profile and antioxidant system were investigated in rats with and without swimming exercise. Sprague-Dawley rats of four experimental groups were fed for 4 weeks diets containing $15\%$ beef tallow and $1\%$ cholesterol; control without garlic and exercise, Go with $2\%$ garlic alone, Ex with exercise alone, GoEx with $2\%$ garlic and exercise. Rats were trained 40 min a days a days a week. Group Ex and GoEx showed significant lowering in body weight gain and fat accumulation. In Go, Ex and GoEx, plasm TG and LDL-C were lower and HDL-C was higher, although not significantly, compared to levels in control. Total cholesterol was significantly reduced in group Go, and Ex and GoEx were lower than control. The total/HDL cholesterol ratio was also found to be significantly different, decreasing the ratios in Go, Ex and GoEx. The hepatic TBARS increased significantly in group Ex $(51.7{\pm}3.43nM/g\;liver)$, while TBARS in Go and GoEx were low $(35.68{\pm}3.61,\;39.30{\pm}5.55nM/g\;liver)$ and similar to control's one. The activity of hepatic SOD in Go and GoEx tended higher than control and Ex without garlic. The hepatic catalase showed significantly the highest activity in Go. Activity of GSH-px was significantly low in Ex with $0.14{\pm}0.03$ unit/mg protein, and control, Go and GoEx had higher activities of $0.23{\pm}0.08,\;0.20{\pm}0.07,\;0.22{\pm}0.01\;unit/mg$ protein, respectively. Lower activities of antioxidant enzymes in Ex are likely to associated with the highest level of TBARS. It seems that a decrease in TBARS in GoEx relative to Ex was related to the increase in GSHpx and SOD with garlic supplemented, which led to compensate the oxidative stress from exercise. The results suggests that exercise or garlic supplement exerts blood lipid attenuating effect. In adition, garlic supplementation could strengthen the antioxidant potential against exercise-induced oxidants, partly by modulating oxidant enzyme activity. These effects of garlic may make it a beneficial agent on CVD.

• Membrane Journal
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• v.28 no.2
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• pp.105-112
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• 2018

In this study, PTMSP-GO composite membranes were prepared by the addition of GO (graphene oxide) into PTMSP [poly (1-trimethylsilyl-1-propyne)] having high gas permeability, to study of gaseous membrane using GO. Gas permeation properties for $N_2$, $CH_4$, $CO_2$ were investigated by increasing the amount of GO in the PTMSP. PTMSP-GO composite membranes had higher gas permeability in the order of $N_2$ < $CH_4$ < $CO_2$. The gas permeation tendency of $N_2$, $CH_4$, and $CO_2$ increased as the content of GO increased from 0 to 10 wt%, but the gas permeability decreased as increased from 10 to 30 wt%. In the range of low GO contents, the gas permeability decreased due to the decrease of diffusivity because GO acts as a barrier in the composite membrane, and the gas permeability increased due to the void at the interface above the content range. And $CO_2$ has an affinity with -COOH of GO, the selectivity ($CO_2/N_2$) and the selectivity ($CO_2/CH_4$) gradually increase with increasing GO content. And the selectivity($CO_2/N_2$) showed the highest selectivity at 10.6 for PTMSP-GO 10 wt% and the selectivity ($CO_2/CH_4$) showed the highest selectivity at 3.4 for PTMSP-GO 20 wt%. However, above a certain amount of GO, selectivity ($CO_2/N_2$) and selectivity ($CO_2/CH_4$) decreased because the coagulation phenomenon between GO was increased and the solubility effect of $CO_2$ decreased. The PTMSP-GO 20 wt% composite membrane exhibited enhanced gas permeation characteristics with increased $CO_2$ permeability and selectivity ($CO_2/CH_4$) over PTMSP membrane.

• Biomedical Science Letters
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• v.12 no.4
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• pp.385-391
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• 2006

Heterotrimeric GTP binding proteins (G proteins) mediate signals generated by neurotransmitters and hormones Among G proteins, Go is found in a large quantity in brain and growth cone membranes of neurons. In spite of its abundance in neurons, the role of Go is not fully understood. In our previous study, we identified promyelocytic leukemia zinc finger protein (PLZF) as an interacting partner of alpha subunit of Go ($Go{\alpha}$) and confirmed their interaction employing several biochemical assays. To date, it is reported that PLZF functioned as a cell growth suppressor and a transcription repressor. To determine effect of $Go{\alpha}$ and PLZF interaction on the cellular function of PLZF, we performed luciferase reporter gene assay and BrdU incorporation assay. Co-expression of $Go{\alpha}$ and PLZF synergistically increased the effect of PLZF alone. These results suggest that $Go{\alpha}$ may act as cellular activator of PLZF. This novel feature of Go may provide insights into understanding diverse role of Go-coupled receptor as well as its cellular actions.

• Polymer(Korea)
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• v.38 no.2
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• pp.180-187
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• 2014

Nanocomposites including graphene oxide (GO) and conducting polymers (PPy, PANI and PEDOT) were prepared via an in-situ chemical polymerization process, and their characteristic properties depending upon the change of conducting polymer (CP) content were analyzed. A confirmation was made on not only the functional groups formed in GO but also the presence of CP existent in the nanocomposites. The molecular interaction between GO and poly(4-styrene sulfonic acid) (PSSA) or CP in the nanocomposites was proposed. With the increase of PEDOT content in the GOPSS/PEDOT nanocomposite, the estimated value of $I_D/I_G$ regarding the Raman analysis of them was decreased and a major change of their Raman spectra characteristic peaks was observed. In the GO-PSS/PEDOT nanocomposite, PEDOT molecules made an exfoliation of GO-PSSA layers and thus they were intercalated among layers. Such a unique molecular morphology induced the highest electrical conductivity for the GO-PSS/PEDOT nanocomposite among three kinds of nanocomposites prepared in this study. It is also noted that the uniform morphology confirmed in this study helped a thermal stability improvement in the nanocomposite due to the presence of GO or GO-PSSA acting as a thermal barrier.

• Membrane Journal
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• v.28 no.4
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• pp.233-242
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• 2018

To study gas membrane using GO (graphene oxide), the PEBAX [poly(ether-block-amide)]-GO polymer composite membrane was prepared by adding GO to PEBAX. Through this composite membrane, gas permeation characteristics for $H_2$, $N_2$, $CH_4$, and $CO_2$ were studied. As a result of the gas permeation test, the permeability of $N_2$, $CH_4$, and $CO_2$ to PEBAX-GO composite membranes gradually decreased as the GO content increased. On the other hand, the gas permeability of $H_2$ increased with the increase of GO content, and it was 21.43 barrer at the GO content of 30 wt%, which was about 5 times higher than that of PEBAX membrane. This is because the GO was easier to operate with a fast and selective gas transport channel for $H_2$ than other gases. The increased selectivity ($H_2/N_2$) and selectivity ($H_2/CH_4$) were influenced by the diffusion selectivity by the permeate gas size. The increased selectivity ($CO_2/N_2$) and selectivity ($CO_2/CH_4$) were more influenced by the solubility selectivity due to the affinity of $CO_2$ and GO for -COOH.