• Journal of The Korean Society of Clinical Toxicology
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• v.13 no.2
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• pp.111-116
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• 2015

Veratrum patulum has toxicological relevance because of the potential for misidentification of this plant as mountain garlic. Veratrum patulum has an ester-alkaloid that provokes cardiac arrhythmias by excessive vagal stimulation and depression of the sinoatrial and atrioventricular nodes of the heart and hypotension, cardiomegaly. We report on a retrospective case of successful outcome in patients with veratrum patulum poisoning through active treatment from the early phase after ingestion. We report on a case involving a patient who experienced dizziness, dyspnea, hypotension, and elevation of cardiac enzyme, cardiomegaly. These cases were kept under observation and generally recovered with supportive care. We report on cases of veratrum patulum poisoning with review of literature.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.793-797
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• 2005

This study was undertaken to examine the feasibility of recycling waste concrete fine aggregate to prepare polymer-modified mortars. The specimens of polymer-modified mortars were prepared by using styrene-butadiene rubber(SBR) latex and polyacrylic ester(PAE) emulsion as a polymer modifier. The formulations for specimens were prepared with various replacing ratios of waste concrete fine aggregates as parts of standard sand and various polymer cement ratios. For the evaluation of the performance of polymer-modified mortars, various physical properties were investigated. As a results, water cement ratio of polymer-modified fresh mortars increased with an increase of recycled fine aggregate, but decreased with an increase of polymer modifiers. The compressive and flexural strengths of polymer-modified mortars decreased with an increase of recycled fine aggregate, but flexural strengths increased with an increase of polymer modifiers.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.4
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• pp.297-302
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• 2009

We have successfully fabricated the alumina thick films using inkjet printing processes without a high temperature sintering process. Alumina suspension as dielectric ink was formulated by combining nano-sized alumina powders with an anionic polymer dispersant in formamide/water as co-solvent. The thickness of the printed alumina thick film was measured at around 5 um by field emission scanning electron microscope. The calculated packing density of 68.5 % from the printed alumina thick film was much higher than the same films fabricated by conventional casting or dip coating processes. Q factor of the dielectrics thick film infiltrated with cyanate ester resin was evaluated by impedance analyzer.

• Natural Product Sciences
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• v.25 no.4
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• pp.354-357
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• 2019

Toxicodendron vernicifluum, also called as Rhus verniciflua is a deciduous tree belonging to Anacardiaceae family. Two new caffeoyl threonate esters, rhuseols A (1) and B (2), together with 5-O-(E)-caffeoylquinic acid methyl ester (3) were isolated from the leaves of T. vernicifluum. The structures of isolated compounds were established by using 1D and 2D NMR in combination with HR-ESI-MS. Compounds 1 - 3 showed DPPH radical scavenging effects with IC₅₀ values of 47.9, 107.8 and 15.4 μM, respectively. Taken together, these compounds might contribute to the antioxidant properties of the leaves of T. vernicifluum, which will be useful for various oxidative stress mediated diseases.

• Textile Coloration and Finishing
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• v.26 no.3
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• pp.272-276
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• 2014

The functional materials have been developed as a promising research topic toward the end uses for organic materials and applications. In this study, fluorescein based dye was synthesized by three step reaction. We have designed and synthesized the colorimetric dye through the reactions of fluorescein and methoxy group and ethylene diamine and squaric acid. The structure of the non-fluorescent spirolactam was elucidated by $^1H$-NMR, LC-Mass and FT-IR analyzes. Further studies are in progress to understand the effects of various substituent during the recognition process and to develop fluorescein based sensors for cations or anions.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.360-363
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• 1994

A colorimetric assay for $\gamma$-glutamyl transpeptidase ($\gamma$-CTP; E.C 2.3.2.2) employing 2, 4, 6-trinitrobenzene sulfonate (TNBS) to detect the amount of disappeared acceptor via transpeptidation, has been developed. Under the experimental conditions using L-$\gamma$-glutamyl ethyl ester and L-phenylalanine as $\gamma$-glutamyl donor and acceptor, respectively, it was found that the decreased absorbance of yellow color at 420 nm was strictly related to the amount of L-$\gamma$-glutamyl-L-phenylalanine (L-$\gamma$-Glu-L-Phe) formed, which was determined by DEAE-cellu-lose column chromatography. Concentrations of the enzyme and $\gamma$-glutamyl products were able to be determinedin the nanogram and nanomoles per milliliter range, respectively, with high precision and reliability. This novel assay system may therefore be a useful means for understanding of catalytic function of the $\gamma$-CTP spectrophotometrically without any usage of sophisticated instruments.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2953-2958
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• 2013

A noble phenylsulfonyl reagent 8 having ${\alpha}$-oxo (cyanomethylene)triphenylphosphorane ylide subunit readily condensed with various alkyl halides under basic conditions to afford ${\beta}$-alkyl-${\alpha}$-oxo-${\beta}$-phenylsulfonyl (cyanomethylene)triphenylphosphorane ylides 9 in excellent yields. These sulfonyl ylides 9 were then reductively desulfonylated with $Na(Hg)/Na_2HPO_4$ in the presence of methanol to provide ${\alpha}$-keto (cyanomethylene)-triphenylphosphorane ylides 2' in good to excellent yields. Our new synthetic approach offers an expeditious access to various ${\alpha}$-keto (cyanomethylene)triphenylphosphorane ylides from alkyl halides utilizing a new phenylsulfonyl reagent as the key reagent under mild reaction conditions in good overall yields.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.292-305
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• 2017

This paper provides the current status of weed science and prospects for the development of weed science based on the research trends presented at the 26th Asian Pacific Weed Science Conference in 2017. Approximately 458 researchers from 25 countries, including Korea, participated in the conference and presented 325 papers in 20 research areas. Major research topics were herbicide resistance, herbicide use, herbicide development, weed ecology, allelopathy, weed management, and exotic weeds. Particularly, there were many presentations and interesting to researchers about the development and use of new herbicides, such as florpyauxifen-benzyl ester, triafamone, fenquinotrione, and tolpyralate. Development of new herbicide formulations and spray methods were suggested as a solution for the population decline in rural area and low labor quality especially in Asia and Pacific regions. In future weedy rice and exotic weeds will be a serious problem in this area so we need to cooperate to make good technical and practical solutions.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.3
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• pp.239-247
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• 2018

Chronic inflammation is known to have effects on various diseases such as gout, cancer, dementia, atopic disease, and obesity. In addition, since some signal cascades involved in the development of inflammation are known to affect the damage and aging of the skin tissue, studies are being conducted actively to control the inflammation mechanism. In order to mitigate or prevent inflammatory response, a number of researches have been made to develop anti-inflammatory materials from some plants. In particular, Stevia rebaudiana produces steviol glycosides (SG), a natural sweetener with a distinctive flavor. Studies on some of SG have been shown to have anti-inflammatory activity. Researchers of this study expected that more SG also possess anti-inflammatory activity, besides stevioside, rebaudioside A, and steviol. In order to confirm this possibility, the researchers screened inhibition activity of various steviol glucosides for NO production in RAW 264.7 cell lines. As a result, steviol ${\beta}-glucopyranosyl$ ester (SGE) showed the highest inhibitory activity among steviol derivatives treated at the same molar concentration. In addition, we found that mRNA expression level of $interleukin-1{\alpha}$ ($IL-1{\alpha}$), $interleukin-1{\beta}$ ($IL-1{\beta}$), cyclooxygenase-2 (COX-2), nuclear factor kappa-light chain-enhancer of activated B cells ($NF-{\kappa}B$) and inducible nitric oxide synthase (iNOS) was also decreased in a dose-dependent manner. These results show that SGE inhibits anti-inflammatory activity and NO production in mouse macrophage RAW 264.7 cells. It was confirmed that SGE has potential to be applied as an anti-inflammatory material.

• Macromolecular Research
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• v.9 no.4
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• pp.238-246
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• 2001

Properties of ternary blends of nylon 6 (Ny6), a thermotropic liquid crystalline polymer (TLCP, poly(ester amide), 20 wt%) and a maleic anhydride grafted polypropylene (2 wt%) (MAPP) were studied under various processing conditions. TLCP was pre-blended with MAPP first and then the binary one blended again with Ny6. The processing temperature of the second mixing was varied. Thermal properties show the partial miscibility of the ternary blend. The morphology of the TLCP phase in the first blending shows mostly in the fibril bundle shape, but varies between droplets and oriented fibrils after the second processing. Some of TLCP phase lost the fibril morphology during the second processing stage. The morphology variation invokes the change in tensile properties. Low extrusion temperature (270$\^{C}$) provides more fibril shapes, which are associated with less deformation in the second stage. The processing temperature effect was more evident when the draw ratio was high. High drawing was applicable due to the stabilizing action of tile compatibilizer.