• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.1
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• pp.113-123
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• 2013

Clothes that retain and emanate body odor feel uncomfortable and unclean; subsequently, the adsorption, desorption and removal amounts of malodorous compounds from fabrics with different polarities were examined. 1-Octen-3-one, octanal and isovaleric acid, which are important malodor compounds from the body, were used as volatile organic compounds (VOC). Samples were prepared with unfinished and ${\beta}$-CD finished cotton, nylon and PET fabrics. The amounts of VOCs retained on the fabrics were measured using headspace GC-MS; in addition, the odor intensity of the samples were evaluated by 10 trained panelists. The amounts adsorbed were estimated by weight gain; however, moisture was found to have a larger effect on the increase in weight than VOCs. The polarity of the VOCs decreased in the order of isovaleric acid, octanal and 1-octen-3-one. Despite the exceptionally large amounts of octanal adsorbed on the nylon sample, the amounts of malodorous compounds adsorbed on fabrics increased with the decreasing VOC molecular weight. The unfinished PET sample adsorbed more VOCs than the unfinished-fabric samples. The odor intensity was mostly weaker in the ${\beta}$-CD finished fabrics than in the unfinished fabrics. The odor intensity of the ${\beta}$-CD finished fabrics was lower than unfinished fabrics. The amount of VOCs that remained on the soiled fabric samples after storing in air for 24 hrs decreased with the increasing VOC vapor pressure. Most VOCs were removed by washing; however, more VOCs were left on the ${\beta}$-CD finished fabrics than unfinished fabrics. The intensity of the odor from the unfinished PET and ${\beta}$-CD finished fabrics was stronger and weaker, respectively, than that of other fabrics, even when the same amounts of VOCs remained.

• Mass Spectrometry Letters
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• v.6 no.3
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• pp.71-74
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• 2015

Low temperature plasma (LTP) ionization mass spectrometry (MS) is one of the widely used ambient analysis methods which allows soft-ionization and rapid analysis of samples in ambient condition with minimal or no sample preparation. One of the major advantages of LTP MS is selective analysis of low-molecular weight, volatile and low- to medium-polarity analytes in a sample. On the contrary, the selectivity for particular class of compound also implies its limitation in general analysis. One of the critical factors limiting LTP ionization efficiency is poor desorption of analytes with low volatility. In this study, a home-built LTP ionization source with Peltier heating sample stage was constructed to enhance desorption and ionization efficiencies of analytes in a sample and its performance was evaluated using standard mixture containing fatty acid ethyl esters (FAEEs). It was also used to reproduce the previous bacterial identification experiment using pattern-recognition for FAEEs. Our result indicates, however, that the bacterial differentiation from FAEE pattern recognition using LTP ionization MS still has many limitations.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.513-519
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• 2007

A vesicle forming polymer, poly(sodium acrylamidoundecanoate) (PSAU) and a water-soluble distyrylbenzene- based fluorophore, TPADSB-C were synthesized and characterized by using UV-vis and photoluminescence (PL) spectroscopy. An inter-chain vesicle formation of PSAU was observed at ~0.01 g/L from N-phenyl naphthylamine fluorescence measurement with changing PSAU concentration in water. Above critical aggregation concentration of PSAU, optical properties of TPADSB-C were investigated to study the microenvironment modulation through dye incorporation in the polymeric vesicle. The emission of TPADSB-C in the presence of PSAU vesicles was blue-shifted and the PL quantum efficiency was increased to 90% due to the microenvironment (e.g. polarity) change in aqueous solution. This study shows that the polymeric vesicle containing molecular fluorophores has a great potential as an efficient, stable and biocompatible labeling tag in biological cell imaging.

• Elastomers and Composites
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• v.49 no.3
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• pp.239-244
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• 2014

Reaction between silica and silane coupling agent without solvent was investigated using transmission mode Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Bis[3-(triethoxysilylpropyl) tetrasulfide] (TESPT) was used as a silane coupling agent. After removing the unreacted TESPT, formation of chemical bonds was analyzed using FTIR and content of reacted TESPT was determined using TGA. Content of the coupling agent bonded to silica increased with increase in the coupling agent content, but the oligomers were formed by condensation reaction between coupling agents when the coupling agent was used to excess. In order to identify bonds formed among silica, coupling agent, and rubber, a silica-coupling agent-BR model composite was prepared by reaction of the modified silica with liquid BR of low molecular weight and chemical bond formation of silica-coupling agent-BR was investigated. Unreacted rubber was removed with solvent and analysis was performed using FTIR and TGA. BR was reacted with the coupling agent of the modified silica to form chemical bonds. Polarity of silica surface was strikingly reduced and particle size of silica was increased by chemical bond formation of silica-coupling agent-BR.

• Molecules and Cells
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• v.37 no.4
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• pp.307-313
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• 2014

Cell migration requires a defined cell polarity which is formed by diverse cytoskeletal components differentially localized to the poles of cells to extracellular signals. Rap-GAP3 transiently and rapidly translocates to the cell cortex in response to chemoattractant stimulation and localizes to the leading edge of migrating cells. Here, we examined localization of truncated RapGAP3 proteins and found that the I/LWEQ domain in the central region of RapGAP3 was sufficient for posterior localization in migrating cells, as opposed to leading-edge localization of full-length Rap-GAP3. All truncated proteins accumulated at the leading edge of migrating cells exhibited clear translocation to the cell cortex in response to stimulation, whereas proteins localized to the posterior in migrating cells displayed no translocation to the cortex. The I/LWEQ domain appears to passively accumulate at the posterior region in migrating cells due to exclusion from the extended front region in response to chemoattractant stimulation rather than actively being localized to the back of cells. Our results suggest that posterior localization of the I/LWEQ domain of RapGAP3 is likely related to F-actin, which has probably different properties compared to newly formed F-actin at the leading edge of migrating cells, at the lateral and posterior regions of the cell.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.5
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• pp.911-921
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• 1997

Recently the interest in natural dyeing has been increased because of the color clarity, natural grace and reactionism in fashion. Indigo dyeing, safflower dyeing and Gal-ott in Cheju-Do become generally known, so the study about the natural dyeing is continued with national intrust and support. In this study, 1 used artemisia for various dyeing tests because we can get it easily. 1 tested the dyeability in wool as well as cotton and silk with wormwood in natural dyeing material. I also dyed nylon with the same material for the comparison of the molecular structure. The mercerization and the chitosan treatment were done in cotton to improve the low dyeability in the natural dyeing. The result of this study are as follows; We have to dye repeatedly to get deep color in natural dyeing, and mordant treatment brought good result in color difference and dyeing fastness. 1. Compared with silk, wool and nylon, the dyeability of cotton was the worse. The color difference of cotton was 18.81 without mordants , and 24.05 with mordant. The dyeability of cotton was much increased by mordants such as potassiumdichromate, copper sulfate, iron sulfate and salt water. The color of cotton was turned into yellow-green in potassium dichromate and yellow-green with deep green in copper sulfate. The mercerization and the chitosan treatment of cotton made the improvement in color, dyeability, laundering fastness, abrasion fastness. 2. The color difference of silk was 3 times as high as cotton. It showed the similar degree with the chitosan treated-cotton. That is to say, silk had good dyeability because it contains amino group and carboxyl group. The dyebility of silk was increased by a mordant such as iron sulfate, potassium dichromate and salt water, Drycleaning fastness showed 5 grade, abrasion-fastness was high over 4~5 grade and sunlight fastness showed 1 grade in all case. 3. The color difference of wool was the best among four fabrics because of 18 kinds of amino acids. It is considered that the sulfate of wool has the polarity and help metal- mordants get the better dyeability such as potassium dichromate, iron sulfate, copper sulfate, and aluminum chloride. The color was reddish-green in potassium dichromate, yellow.greenin iron sulfate and copper sulfate, and yellow in the rest mordants. Drycleaning fastness of wool showed over 4~5 grade, abrasion fastness 5 grade. Sunlight-fastness 1 grade. 4. The dyeability of nylon was almost same because of the similar molecular structure with silk. The clarity of color was poor. The color was yellow-green in copper sulfate and yellow in the rest mordants. Laundering fastness and abrasion-fastness of nylon was good. Sunlight- fastness represented 1 grade.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.85-98
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• 1995

Six malformin B's produced by Aspergillus niger van Tiegh. were separated by HPLC. Their structures determined by the methods of amino acid analyses, mass spectrometry, and two-dimensional NMR were revealed as cyclic pentapeptides structurally related to malformin $A_1$. Both the NMR and MS/MS data suggest that the respective structures of separated malformin B's were as follows; cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-allo-Ile for $B_{1a}$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Leu for $B_{1b}$, cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Leu for $B_2$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Leu for $B_3$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Ile for $B_4$, and cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Ile for $B_5$. Among the malformin B's, the structure of $B_{1b}$ was the same as that of malformin $A_3$ or C. All the malformin B's showed physiological activities in the two assay systems using corn(Zea mays L.) roots and mung bean(Phaseolus aureus Roxb.) hypercotyl segments. The malformin B's with molecular weight 529 were more effective for inducing corn root curvature than those with molecular weight 515. The difference in molecular weight of malformin B's, i.e., the retention time on HPLC, results in the polarity change of the whole malformin molecule which affects the revealation of the malformin activities. In addition, the disulfide form of the malformin B's gives the rigidity of the molecule, whereas the combination of the fourth and the fifth amino acid residues provides the optimal three-dimensional configuration to the malformin receptor of plants. Presumably, these two factors are appeared to be essential for the greatest physiological activity of malformin B's. malformin $B_{1a}$ caused the corn root curvature by 90% at a concentration of $0.25{\mu}M$. However, such differential activities with molecular weight of 529 or 515 of malformin B's were not found in the mung bean hypercotyl segment test. Maximum stimulation of mung bean hypercotyl growth was observed at $0.1{\mu}M$ concentration of malformin B's. The growth of the segments treated with $B_5$ was 154% greater than that of the control.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.989-996
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• 2007

In this study, abiotic transformation of 1-naphthol(1-NP) via oxidative-coupling reaction and its reaction products were investigated in the presence of Mn oxides. The reaction products were characterized for their relative polarity using solvent extraction experiment and reverse-phase HPLC, and for structure using CCMS and LC/MS, and for absorption characteristics using UV-Vis spectrometry. The reaction products present in aqueous phase were more polar than parent naphthol and comprised of 1,4-naphthoquinon(1,4-NPQ) and oligomers such as dimers and trimers. Hydrophilic component present in water phase after solvent$(CH_2Cl_2)$ extractions was identified as naphthol polymerized products having molecular weight(m/z) ranging from 400 to 2,000, and showed similar UV-Vis. absorption characteristics to that of foil fulvic acid. Transformation of 1,4-NPQ, which is non-reactive to Mn oxide, to the polymerized products via cross-coupling reaction in the presence of 1-NP was also verified. In this experimental conditions(20.5 mg/L, 1-NP, 2.5 g/L $MnO_2$, pH 5), the transformation of 1-NP into the oligomers and polymerized products were about 83% of initial 1-NP concentrations, and more than 30% of the reaction products was estimated to be water insoluble fractions, not extracted by $H_2O$ methanol. Results from this study suggest that Mn oxide-mediated treatment of naphthol contaminated soils can achieve risk reduction through the formation of oligomers md polymer precipitation.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.400-403
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• 2002

The fundamental experiments for measuring soft x-ray characteristics from the vacuum capillary are described. These experiments were primarily performed in order to generate line spectra such as x-ray lasers. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, a turbo-molecular pump, and a radiation tube with a capillary. A high-voltage condenser of 200 nF in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. During the discharge, weakly ionized plasma forms on the inner and outer sides of a capillary. In the present work, the pump evacuates air from the tube with a pressure of about 1 mPa, and a demountable capillary was developed in order to measure x-ray spectra according to changes in the capillary length. In this capillary, the anode (target) and cathode elements can be changed corresponding to the objectives. The capillary diameter is 2.0 mm, and the length is adjusted from 1 to 50 mm. When a capillary with aluminum anode and cathode electrodes was employed, both the cathode voltage and the discharge current almost displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -10.8 kV and 4.7 kA, respectively. The x-ray durations observed by a 1.6 ${\mu}$m aluminum filter were less than 30 ${\mu}$s, and we detected the aluminum characteristic x-ray intensity using a 6.8 ${\mu}$m aluminum filter. In the spectrum measurement, two sets of aluminum and titanium electrodes were employed, and we observed multi-line spectra. The line photon energies seldom varied according to changes in the condenser charging voltage and to changes in the electrode element. In the case where the titanium electrode was employed, the line number decreased with corresponding decreases in the capillary length. Compared with incoherent visible light, these rays from the capillary were diffracted and diffused greatly after passing through two slits.

• Journal of Life Science
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• v.18 no.6
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• pp.764-769
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• 2008

Mutations in the human connexin 32 (Cx32) gene are responsible for X-linked Charcot-Marie-Tooth (CMTX) disease. Although over 300 different mutations have been identified the detailed molecular etiology of CMTX disease is poorly understood. Several studies reported that connexin membrane channels share most biophysical properties with their parental gap junction channels. In this study, two connexin mutant membrane channels (one mutant channel called the M34T channel in which the methionine residue at the $34^{th}$ position of the Cx32 protein is replaced with threonine residue and the other mutant channel called the T86C channel in which the threonine residue at the $86^{th}$ position is replaced with cysteine residue) associated with CMTX mutations were characterized at the single-channel level instead of using mutant gap junction channels. The biophysical properties of the M34T channel were very similar to those of the gap junction channel formed by M34T mutation. In addition, the mutant membrane channel study revealed the reversal of the gating polarity, the loss of fast gating and the gain of slow gating. The T86C channel also behaves like its parental wild type Cx32 membrane channel. Taken together, these results suggest that a study using connexin membrane channels is useful to characterize CMTX mutants.