• Journal of Life Science
• /
• v.6 no.2
• /
• pp.104-110
• /
• 1996

The present study was conducted to elucidate the functional property of tea extract obtained from tea extracts, semi-fermented tea(oolong tea) and fermented tea(black tea). Tea extracts exhibited remarkable nitrite-scavenging actions, and the action increased with the increased of the amount of tea extracts. The nitrite-scavenging actionof tea extracts showed pH dependent, highest at pH 1.2 and lowest at pH6.0. The nitrite-scavenging rate in tea extracts/amine/nitrite systems proved to be faster than that in amine/nitrite systems. To screen the nitrite-scavenging factors, tea extracts were fractionated into water-soluble, methanol-soluble, methanol-precipitate and crude catechin fraction. Among these fractions of tea extracts, the crude catechin fraction possessed greater nitrite-scavenging action than the other fractions. The nitrite-scavenging action of tea extracts increased with the contents of total phenols and an absorbance at 280nm, nitrite-scavenging factors were supposed to be and catechins in tea polyphenol compounds.

• Korean Journal of Materials Research
• /
• v.23 no.11
• /
• pp.661-665
• /
• 2013

We investigated the characteristics of electroless plated Cu films on screen printed Ag/Anodized Al substrate. Cu plating was attempted using neutral electroless plating processes to minimize damage of the anodized Al substrate; this method used sodium hypophosphite instead of formaldehyde as a reducing agent. The basic electroless solution consisted of $CuSO_4{\cdot}5H_2O$ as the main metal source, $NaH_2PO_2{\cdot}H_2O$ as the reducing agent, $C_6H_5Na_3O_7{\cdot}2H_2O$ and $NH_4Cl$ as the complex agents, and $NiSO_4{\cdot}6H_2O$ as the catalyser for the oxidation of the reducing agent, dissolved in deionized water. The pH of the Cu plating solutions was adjusted using $NH_4OH$. According to the variation of pH in the range of 6.5~8, the electroless plated Cu films were coated on screen printed Ag pattern/anodized Al/Al at $70^{\circ}C$. We investigated the surface morphology change of the Cu films using FE-SEM (Field Emission Scanning Electron Microscopy). The chemical composition of the Cu film was determined using XPS (X-ray Photoelectron Spectroscopy). The crystal structures of the Cu films were investigated using XRD (X-ray Diffraction). Using electroless plating at pH 7, the structures of the plated Cu-rich films were typical fcc-Cu; however, a slight Ni component was co-deposited. Finally, we found that the formation of Cu film plated selectively on PCB without any lithography is possible using a neutral electroless plating process.

• The Journal of the Korea Contents Association
• /
• v.15 no.5
• /
• pp.47-54
• /
• 2015

The following research analyzes that the level of self-monitoring have an influence on user experience about website. For this research, university students participated in a survey where they evaluated user experience -usability, aesthetics, pleasure- about the new screen images of two homepages of differences in brand recognizability. The "self-monitoring(high/low, except for middle)" and the "brand recognizability(high/low, except for middle)" were set as independent variables and the "usability | deviation |", the "aesthetics | deviation |", the "pleasure | deviation |" were set as the dependent variables. Results, as with new screen images of homepage, there were significant differences in the usability and aesthetics based on the level in self-monitoring. Especially, when level of brand recognizability is low, there was more differences in the usability and aesthetics based on the level in self-monitoring. However, the influence of pleasure on self-monitoring was insignificant.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2002.10a
• /
• pp.162-172
• /
• 2002

Schizosaccharomyces pombe is suited for the study of cytokinesis as it divides by forming a septum in the middle of the cell at the end of mitosis. To enhance our understanding of the cytokinesis, we have carried out a genetic screen for temperature-sensitive S. pombe mutants that show defects in septum formation and cell division. Here we present the isolation and characterization of a new temperature-sensitive mutant, sun1(septum uncontrolled), which undergoes uncontrolled septation during cell division cycle at restrictive temperature $(37^{\circ}C)$. In sun1 mutant, actin ring and septum are positioned at random locations and angles, and nuclear division cycle continues. These observations suggest that the sun] gene product is required for the proper placement of the actin ring as well as precise septation. The sun] mutant is monogenic recessive mutation unlinked to previously known various cdc genes of S. pombe. In a screen for $sunl^+$ gene to complement the sun] mutant, we have cloned a gene, $susl^+$(suppressor of sun1 mutant), that encodes a protein of 689 amino acids. The predicted amino acid sequence of $susl^+$ gene is similar to the human hMadlp and Saccharomyces cerevisiae Mad1p, a component of the spindle checkpoint in eukaryotic cells. The null mutant of $susl^+$ gene grows normally at various temperatures and has the increased sensitivity to anti-microtubule drug, while $susl^+$ mutant shows no sensitivity to microtubule destabilizing drugs. The putative S. pombe Sus1p directly interacts with S. pombe Mad2p in yeast two-hybrid assays. These data suggest that the newly isolated susr gene encodes S. pombe Mad1p and suppresses sun] mutant defective in controlled septation in a cell division cycle.

• Journal of Ginseng Research
• /
• v.24 no.1
• /
• pp.29-34
• /
• 2000

The effects of each component (water extracts, alcohol extracts, lipophillic extracts, total saponin, panaxadiol, panaxatriol) of red ginseng on the antioxidative enzyme activities were investigated in the liver in order to screen antioxidative components of red ginseng. 20∼25g ICR mouse which were pretreated with 50 mg/kg body weight of red ginseng component for 15 days. The ability of red ginseng component to protect against oxidative damage to the mouse liver was examined by determining the level of lipid peroxidation (MDA), hydroperoxide (H$_2$O$_2$) and the activities of superoxide dismutase (SOD), catalase. The hepatic total-SOD activity was highest in lipophilic extracts group and panaxadiol group next (p<0.01). The content of hepatic hydroperoxide was lowest in the order of panaxatriol group and alcohol extracts group (p < 0.01). The hepatic catalase activity in the liver was highest in order of lipophillic extracts group (p <0.01) and total saponin group (p<0.05). Finally the lipid peroxidation (MDA) level was lowest in lipophillic extracts group, alcohol extracts group and panaxadiol next (p <0.01). In conclusion, the order of effectiveness of antioxidants was to be lipophillic extracts>panaxadiol >total saponins.

• Journal of Nutrition and Health
• /
• v.36 no.1
• /
• pp.83-92
• /
• 2003

Improving dietary patterns, na, in turn, improving nutritional status, is now viewed as a key to improve public health and to prevent chronic diseases. There has been a peat needs to assess diet quality to identify nutritional risk group, however, little research has been done on methods to assess overall diet quality. The purpose of this study was to develope a mini dietary assessment (MDA) index for evaluation of overall dietary quality. A 10-component system was devised based on dietary guidelines and food Tower for Koreans. The system contained 4 food elements of which use is encouraged, such as milk, meat, vegetables, fruits, and 3 food elements of which use is limited, such as fat, salt, or sugar. Also the included were elements on dietary regulation and variety. A subject is to check one of ‘always' 'generally'seldom', which has score of 5, 3, and 1, respectively, so the total possible index score is 50. This index is to use without dietary survey and is to use even by non-nutritionist. A sample of 432 healthy males and females in their 30's and 40's contributed diet intake data based on 24-hour recall for the validation of MDA. The mean MDA score was 31.34 of a possible 50 points. The main nutrients for each MDA component was correlated very well with the results of 24-hour recall. Also, very good correlation was found between healthy eating index (HEI) score and MDA score. However, some of MDA components were needed a modification of term or/and statement. So the Uh was revised and another effort for validation was made with new sample of 169 subjects and even better correlation was found. The revised MDA could be used with minor modification to assess diet quality and to screen nutritional status. (Korean J Nutrition 36(1): 83-92, 2003)

• Journal of Hydrogen and New Energy
• /
• v.21 no.6
• /
• pp.533-539
• /
• 2010

Ni-YSZ supported button cells were prepared by spray-coating YSZ and screen-printing YSZ-LSM powder as an electrolyte and oxygen electrode on Ni-YSZ cermet disks. In order to identify the polarization loss mechanism in high temperature electrolysis current-voltage characteristics coupled with electrochemical impedance spectroscopy were investigated as a function of temperature, current load, and the humidity. The effects of the different current collectors of platinum and silver for oxygen electrodes were compared. With Ag current collector two polarization losses were distinguished. The high frequency component was attributed to the Ni-YSZ cermet which was less susceptible to temperature variation but increasing in loss with humidity. The lower frequency component was attributed to the LSM electrode. Platinum current collector led to a much lower polarization loss.

• Korean Journal of Clinical Laboratory Science
• /
• v.36 no.2
• /
• pp.158-162
• /
• 2004

The over-preparation of blood for elective surgery causes some problems such as returning of blood, inefficient task and loss of reagents. In recent blood transfusion practice, there has been changing patterns of blood use in elective surgery as various side effects of transfusion have become known and operation techniques are developed. This study was performed to evaluate the optimal utilization of blood for various elective and/or emergency surgery. We surveyed the quantity of blood transmitted to wards, returned to blood bank, and the number of crossmatching test done for the elective surgery of the patients at the D. University Hospital, the tertiary teaching hospital from August 1, 2001 to October 31, 2001. Crossmatched to transfusion ratio (C/T ratio) was calculated, in which C means the unit of accomplished crossmatching test and T means the unit of transfused blood component. The unit of transfused blood was analysed in terms of issuing time, sex, age, clinical department, and blood component type. The usage of bloods for the emergency surgery was also analyzed. In our study, C/T ratio was highest on Monday (1.54) and Tuesday (1.53), and higher in female patients(1.54) than in male patients (1.32). No significant relationship was observed between age groups. Among clinical departments, thoracic and cardiovascular surgery showed the highest C/T ratio (1.54). From above results, we could be sure that the management of transfusion practice was relatively appropriate in recent years, although the entire introduction of type and screen (T&S) method was desirable. If the T&S method is performed, the C/T ratio would be almost 1.00 and it would also relieve the duty of blood bank.

• The Bulletin of The Korean Astronomical Society
• /
• v.36 no.2
• /
• pp.73.2-73.2
• /
• 2011

We present a new database of absorption and emission-line measurements based on the entire spectral atlas from the Sloan Digital Sky Survey (SDSS) 7th data release of galaxies within a redshift of 0.2. Our work makes use of the publicly available penalized pixel-fitting(pPXF) and gas and absorption line fitting (gandalf) IDL codes, aiming to improve the existing measurements for stellar kinematics, the strength of various absorption-line features, and the flux and width of the emissions from different species of ionized gas. Our fit to the stellar continuum uses both standard stellar population models and empirical templates obtained by combining a large number of stellar spectra in order to fit a subsample of high-quality SDSS spectra for quiescent galaxies. Furthermore, our fit to the nebular spectrum includes an exhaustive list of both recombination and forbidden lines. Foreground Galactic extinction is implicitly treated in our models, whereas reddening in the SDSS galaxies is included in the form of a simple dust screen component affecting the entire spectrum that is accompanied by a second reddening component affecting only the ionised gas emission. Most notable of our work is that, we provide quality of the fit to assess reliability of the measurements. The quality assessment can be highly effective for finding new classes of objects. For example, based on the quality assessment around the Ha and [NII] nebular lines, we found approximately 1% of the SDSS spectra which classified as "galaxies" by the SDSS pipeline are in fact type I Seyfert AGN.

• Resources Recycling
• /
• v.7 no.4
• /
• pp.35-42
• /
• 1998

Surface mount technology is the biggest theme in the area of deιIronic component. To miniatunze an electronic component, s such as ferrite chip inductor, the cer뼈lic wet process for green-sheet lamination and/or screen printing method through a s solvent medium system is widely used. The preparation and characterization of NiCuZn Ferrite (NCZF) shurry and the green s sheet using the water mixed binder system has been studied. The 21 vol% of NCZF slurry was prepared by a ball milling. The p polyacrylic vinyl copolymer (Mw; 60,000) was used as a binder. Th$\xi$ mixture of distilled water, isopropyl alcohol (IPA) and 2l butoxy ethanol was used as a dispersion medium. The water content of medium varied from about 40% to 80%. As the results. Thc disp$\xi$rston stability of the NCZF slurry was attributed to the free polymer rather than the electrostatic force of the particle. T The viscosity of the NCZF slurry was greatly depended on the ratio of water content in the medium.