• Tribology and Lubricants
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• v.30 no.4
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• pp.224-233
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• 2014

We prepared polyester-polyamines to improve the effect of carbon black dispersibility for use in thermal transfer ink, and synthesized polymeric dispersing agents by two-step reactions. In the first step, we made polyester by polycondensing 1,6-hexanediol and adipic acid. The resulting polymers had carboxylic acid, which was linked with polyamine via an acid-base reaction. We then characterized the polyester-polyamine structure by NMR spectroscopy and Fourier transform infrared spectroscopy (FT-IR). We also determined the basic characterizations such as total acid numbers (TAN) (5.0-67.5 mgKOH/g), hydroxyl values (27.1-67.5 mgKOH/g), and molar masses ($M_n=1.6-8.4kg\;mol^{-1}$) for the polyester and total base numbers (TBN) (15.3-57.1 mgKOH/g), hydroxyl values (33.0-79.8 mgKOH/g), and nitrogen contents (1.02-3.48%) for the polyester-polyamine polymers. We thus prepared thermal transfer ink using carbon blacks and the polyester-polyamine dispersing agents, and evaluated the resulting mixtures for printability, adhesive force, storage stability, ink appearance, ink gloss, and processability. These mixtures showed significant dispersibility for carbon black in the ink. Thus, we concluded that the dispersibility of the polymeric materials depended on the polyamine structure and the hydrophilicity-hydrophobicity distribution of the polymeric dispersants.

• Nutrition Research and Practice
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• v.12 no.1
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• pp.20-28
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• 2018

BACKGROUND/OBJECTIVES: Perilla frutescens (L.) Britton var. (PF) sprout is a plant of the labiate family. We have previously reported the protective effects of PF sprout extract on cytokine-induced ${\beta}-cell$ damage. However, the mechanism of action of the PF sprout extract in type 2 diabetes (T2DM) has not been investigated. The present study was designed to study the effects of PF sprout extract and signaling mechanisms in the T2DM mice model using C57BL/KsJ-db/db (db/db) mice. MATERIALS/METHODS: Male db/db mice were orally administered PF sprout extract (100, 300, and 1,000 mg/kg of body weight) or rosiglitazone (RGZ, positive drug, 1 mg/kg of body weight) for 4 weeks. Signaling mechanisms were analyzed using liver tissues and HepG2 cells. RESULTS: The PF sprout extract (300 and 1,000 mg/kg) significantly reduced the fasting blood glucose, serum insulin, triglyceride and total cholesterol levels in db/db mice. PF sprout extract also significantly improved glucose intolerance and insulin sensitivity, decreased hepatic gluconeogenic protein expression, and ameliorated histological alterations of the pancreas and liver. Levels of phosphorylated AMP-activated protein kinase (AMPK) protein expression also increased in the liver after treatment with the extract. In addition, an increase in the phosphorylation of AMPK and decrease in the phosphoenolpyruvate carboxykinase and glucose 6-phosphatase proteins in HepG2 cells were also observed. CONCLUSIONS: Our results sugges that PF sprout displays beneficial effects in the prevention and treatment of type 2 diabetes via modulation of the AMPK pathway and inhibition of gluconeogenesis in the liver.

• Journal of the Korea Furniture Society
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• v.27 no.1
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• pp.8-14
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• 2016

Increasing concerns of environment need to make change furniture field to more environmentally friendly approach, such as reuse of by-products from wooden products. As it is, the methods of recycling wood for industrial purposes have the advantage of productivity and adaptability. However, the industrial way is required a certain production facility of processing wooden by-products and has possible hygienic problems due to contaminated sources. Many designers have developed their own methods for reuse of wood in unique and artistic ways. Even so, because of confined sources, it could be not enough supply. Therefore, I developed the design methodology utilizing wooden by-products from S Design Company to relieve former ways' problems. The design suggestion took materials from a safe and abundant source. The wooden leftover pieces were connected together with epoxy clay, so previous process traces of furniture are remained as a decorative factor. Moreover, the synthesized material was able to be processed by ordinary woodworking facilities without additional installations. In doing so, console table focused on a commercial purpose and dining table for an artistic objective were successfully fabricated as final suggestions. In consideration of the proposal using wooden furniture leftovers, diverse recycling designs should be investigated for future reference.

• Korean Journal of Pharmacognosy
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• v.50 no.2
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• pp.141-147
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• 2019

The aim of this study was to investigate the potential of Acanthopanax sieboldianum (Makino) Koidz (ACS) as a potent antioxidant and antidiabetic agent. The antioxidative and alpha-glucosidase inhibitory activities were examined using the methanol extracts and solvent fractions from ACS-leaf and ACS-stem. Antioxidative activities were measured by in vitro methods such as DPPH and ABTS radical scavenging activity and superoxide dismutase (SOD) activity. When the chloroform and ethyl acetate fractions of ACS-leaf and ethyl acetate fractions of ACS-stem were compared with the control, the SOD-like activity was impaired even at the low treatment concentrations. In addition, the ethyl acetate fractions of ACS-leaf and ACS-stem showed alpha-glucosidase inhibition activities at low treatment concentrations. Analysis of the major components in the fractions of ACS-leaf and ACS-stem was also performed using HPLC. Finally, astragalin, isoqurecetin, chlorogenic acid and caffeic acid contents were measured. Based on this work, we propose that ACS-leaf and ACS-stem have great potential as natural antioxidant and antidiabetic materials related to health benefits.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.2.1-2.8
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• 2021

Objectives: New premixed bioceramic root repair materials require moisture for setting. Using micro-computed tomography (micro-CT), this study evaluated the filling ability and volumetric changes of calcium silicate-based repair materials (mineral trioxide aggregate repair high-plasticity [MTA HP] and Bio-C Repair, Angelus), in comparison with a zinc oxide and eugenol-based material (intermediate restorative material [IRM]; Dentsply DeTrey). Materials and Methods: Gypsum models with cavities 3 mm deep and 1 mm in diameter were manufactured and scanned using micro-CT (SkyScan 1272. Bruker). The cavities were filled with the cements and scanned again to evaluate their filling capacity. Another scan was performed after immersing the samples in distilled water for 7 days to assess the volumetric changes of the cements. The statistical significance of differences in the data was evaluated using analysis of variance and the Tukey test with a 5% significance level. Results: Bio-C Repair had a greater filling ability than MTA HP (p < 0.05). IRM was similar to Bio-C and MTA HP (p > 0.05). MTA HP presented the largest volumetric change (p < 0.05), showing more volume loss than Bio-C and IRM, which were similar (p > 0.05). Conclusions: Bio-C Repair is a new endodontic material with excellent filling capacity and low volumetric change. The gypsum model proposed for evaluating filling ability and volumetric changes by micro-CT had appropriate and reproducible results. This model may enhance the physicochemical evaluation of premixed bioceramic materials, which need moisture for setting.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_1
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• pp.897-906
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• 2020

This research focuses on the physicochemical characteristic of fermentation of Aloe Saponaria. The fermentation process applied in this study had 2 variation, depends on the aloe part as the materials (bottom, middle, and tip) and the initial sugar content (24% and 0%) used. Tests are conducted using uinkin fermented powder, sugar, salt, and distilled water as fermenting agent. The results indicate that change in physicochemical properties of aloe's skin was larger than in aloe's gel as fermentation materials. In contrast, there was no significant change in aloe's leaf during the process. A lso, aloes with intial sugar condition of 24% show better results than which without sugar addition in fermentation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.703-704
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• 2012

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.212-213
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• 2005

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.04a
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• pp.84-85
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• 2005

• Journal of Adhesion and Interface
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• v.3 no.3
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• pp.41-50
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• 2002