• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.564-569
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• 2012

Selenium was initially considered toxic to humans, but it was then discovered that selenium is essential for normal life processes. Selenium plays important roles in antioxidants. It is expected that chitosan microcapsules containing nano-selenium will be able to be used as a key material in bio-medical and cosmetic applications. The high concentration of chitosan derivatives guarantees increased antioxidative activity. Both inorganic and organic forms of selenium can be nutritional sources. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. The objective of this experiment was to study the antioxidative activity of chitosan nano-selenium. Our experiments were divided into five groups, in the presence of various concentrations(0.1%, 0.3%, 0.5%, 0.7%, and 0.9%) of chitosan. We performed an assessment of the antioxidant properties and cytotoxicity of respective concentrations of chitosan nano-selenium. The antioxidant activity was examined by the free radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl(DPPH) assay. The cytotoxicity effect was measured by means of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. As a result, the electron donating abilities of 0.1%, 0.3%, 0.5%, 0.7%, and 0.9% of chitosan nano-selenium exhibited effective andioxidant scavenging activity at 12.5 ${\mu}g/m{\ell}$ against DPPH radicals. 0.3% chitosan nano-selenium did not show cytotoxicity on human keratinocytes. In general, the cytotoxicity of 0.1% and 0.9% chitosan nano-selenium showed the lowest effects. Though low cytotoxicity of 0.5% and 0.7% chitosan nano-selenium exhibited 29.67% and 38.4% against human keratinocytes on adding 100 ${\mu}g/m{\ell}$ and 50 ${\mu}g/m{\ell}$, respectively, cell vitality was recovered with 200 ${\mu}g/m{\ell}$. These findings support the notion that chitosan nano-selenium may be useful as a new active ingredient source for bioactive compounds.

• Analytical Science and Technology
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• v.28 no.6
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• pp.409-416
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• 2015

ICP-AES has been used in many laboratories due to the advantages of wide calibration range and multi-element analysis, but it may give erroneous results and suffer from spectral interference due to the large number of emission lines associated with each element. In this study, certified reference materials (CRMs) and field samples were analyzed by ICP-AES and HG-AAS according to the official Korean testing method for soil pollution to investigate analytical problems. The applicability of HG-ICP-AES was also tested as an alternative method. HG-AAS showed good accuracies (90.8~106.3%) in all CRMs, while ICP-AES deviated from the desired range in CRMs with low arsenic and high Fe/Al. The accuracy in CRM030 was estimated as below 39% at the wavelength of 193.696 nm by ICP-AES. Significant partial overlaps and sloping background interferences were observed near to 193.696 nm with the presence of 50 mg/L Fe and Al. Most CRMs were quantified with few or no interferences of Fe and Al at 188.980 nm. ICP-AES properly assessed low and high level arsenic for field samples, at 188.980 nm and 193.696 nm, respectively. The importance of the choice of measurement wavelengths corresponding to relative arsenic level should be noted. Because interferences were affected by the sample matrix, operation conditions and instrument figures, the analysts were required to consider spectral interferences and compare the analytical performance of the recommended wavelengths. HG-ICP-AES was evaluated as a suitable alternative method for ICP-AES due to improvement of the detection limit, wide calibration ranges, and reduced spectral interferences by HG.

• Economic and Environmental Geology
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• v.50 no.1
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• pp.1-14
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• 2017

The analytical conditions including surface state, moisture effect, and device condition were investigated for applying Short Wave Infrared(SWIR) spectroscopy to the field survey. Among the three surface state of samples (exposed surface, cutting face and powder), both spectra from the exposed surface and cutting face are almost identical whereas spectral variation was detected in powder sample. Over 24-hours-dryring of the wet sample at room temperature, the samples show a similar spectrum with that of dry condition. The result suggests that outcrop samples mighty be dried for 24 ~ 48 hours depending on the wetness of outcrop. The bright minerals could produce stable spectra with 10 times measurements as default value of the device under SWIR spectroscopy but the dark minerals would require about 10 seconds, which corresponds to 100 times measurements to get the reliable spectra. The position and shape 2,160 ~ 2,330 nm and/or other spectral features of hydrothermal alteration minerals by SWIR spectroscopy could be used for a classification of hydrothermal alteration zone in the field. Absorption peaks in 2,160 ~ 2180 nm are useful for identifying (advanced) argillic zone by spectral characteristics of kaoline, dickite, pyrophyllite, and alunite. Absorption peaks in 2,180 ~ 2,230 nm are able to define muscovite, sericite, and smectite, which are key alteration minerals in phyllic zone. Absorption peaks in 2,230 ~ 2,270 nm can be used to recognize prophylitic zone where chlorite and epidote occur. Absorption peaks of other principle minerals such as talc, serpentine, amphibole, and carbonate group are mainly detected within the wave length of 2,270 ~ 2,330 nm. This result indicates that the spectra of these minerals need to be carefully interpreted.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1725-1731
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• 2016

This study was carried out to investigate the effects of steam-drying on antioxidant compounds and antioxidant activity of Alliun hookeri root (AHR). The yield of methanolic extracts, total phenolic content (TPC), browning intensity (280 nm and 420 nm), and organosulfur compound contents (alliin and cycloalliin) in raw and steam-dried AHRs were 10.71~37.40%, $15.53{\sim}36.36{\mu}g/mg$, 0.48~2.09, 0.01~0.25, $1.46{\sim}700.61{\mu}g/mg$, and $1,173.95{\sim}2,182.60{\mu}g/mg$, respectively. Yield, TPC, and browning intensity of AHRs increased by steam-drying, whereas organosulfur compound contents decreased. Of all methanolic extracts from raw and steam-dried AHRs, four-time steam-drying showed the lowest $EC_{50}$ values (0.43, 7.53, 0.34, and 0.48 mg/mL, respectively) for DPPH radical scavenging activity, ABTS radical scavenging activity, SOD-like activity, and reducing power, whereas four-time steam-drying resulted in the highest TPC ($36.36{\mu}g/mg$) and browning intensity (2.09 and 0.25 at 280 and 420 nm, respectively). The antioxidant activities of methanolic extracts from raw and steam-dried AHRs were closely correlated with their TPC, browning intensity, and organosulfur compound content, showing correlation determination coefficient ($R^2$) values higher than 0.82. As a result, four-time steam-drying of AHRs could be useful as potential antioxidant sources.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.1013-1016
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• 1995

The color stability of betacyanins and effects of antioxidants from Opuntia dillenii Haw were determined in the fruit juice at temperature up to $90^{\circ}C$. The absorption maxima of betacyanins occurred between 536 nm and 538 nm. When fruit juice was heated at $90^{\circ}C$ for various times, the red color gradually diminished and the absorption maxima slightly shifted toward uv region. The kinetic analysis of the data obtained indicated that the discoloration for betacyanins obeyed first order reaction pattern, when the thermal stability test was performed at $50{\sim}90^{\circ}C$. And the rate constant increased from $1.56{\times}10^{-3}/min\;to\;71.91{\times}10^{-3}/min$ with the half-life decreasing from 444.23 min to 9.64 min. The results also indicated that the thermal stability of pigment decreased with increasing temperature. The energy of activation was 10.94 kcal/mole for the pigment. N-propyl gallate, L-cysteine, and ascorbic acid were added to cactus fruit juice at concentrations of $0.01{\sim}0.3%$ at different temperatures. Npropyl gallate and L-cysteine had a little antioxidant effect on betacyanins stability at $50^{\circ}C\;and\;70^{\circ}C$, whereas ascorbic acid had a great antioxidant effect with the half-life value of 2 to 10 times to that of the control.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.2
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• pp.69-80
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• 1986

In order to analyse the color preference quantitatively, specially with reference to the subjects in the age of twenties, 100 subjects(M=50, F=50) that unconsidered other factors were adopted and responded to 4 items of the questionaire. The item no. 1 was to investigate the most prefered color on the white background, no. 2 was to most preferred stimulation -level of lightness in the same hues, no. 3 was to most prefered color on 5 different backgrounds -grey, blue, pink, yellow, and yellow green-, and no. 4 was same as no. 3 but with different color-arrangement Materials for item 1 and 3 were made with transparent acryl-boards(30cm$\times$30cm), on which 16 color chips arranged on circle, for item 4 on lattice, and for item 2 with 16 white boards(8cm$\times$21cm), on which 7 color chips of different lightness-level arranged. Reflectance(Y) and color coordinate(x, y) of all color chips measured with color difference meter were transfered into wavelength(nm), exitation purity(%), and Munsell's value. The results may be summarized as follows: 1) Most prefered color was bluish green with wave1ength about 500nm. As increasing of exitation purity of color, more prefered. 2) When there were 7 different levels of lightness in the same hues, the relationship between the number of preference and the stimulation was inverted U-shaped. 3) With changing the background -color, the prefered colors were contrasting when backgrounds were low or high intensity-stimulation and familiar colors when backgrounds were medium intensity.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.2
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• pp.394-400
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• 2014

In this study, we fabricated ITZO thin films on glass substrates with various RF power from 30 to 60W and investigated the electrical, optical and structural properties. ITZO thin film deposited at 50W exhibited the largest figure of merit ($10.52{\times}10^{-3}{\Omega}^{-1}$) and then its resistivity and sheet resistance were $3.08{\times}10^{-4}{\Omega}-cm$ and $11.41{\Omega}/sq.$, respectively. As results of optical characterization, average transmittance of all ITZO thin films were over 80%. ITZO thin films had amorphous structure regardless of the RF power. The FESEM and AFM results showed that all ITZO thin films have a very smooth surface having no cracks and defects and the film deposited at 50W exhibit the smallest surface roughness of 0.254nm. We found that a amorphous ITZO thin film is a very promising material for replacing ITO in the next display device such as OLED.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.12-18
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• 2005

This study was carried out to evaluate anthocyanine contents, effective components and major botanical characteristics of the new developed colored rices. Characteristics of colored rice lines showed variation in culm length and spikelets per panicle in CNU39, panicle length in CNU43, 1,000 grain weight in CNU90, and yield per plant in CNU119 were highly compared to the Check, Heugjinjubyeo. Relative optical density(ROD) of Heugjinjubyeo was the highest at 530 nm, followed by CNU71, CNU73 and CNU119. The high peaks of ROD of Heugjinjubyeo and CNU71 appeared at 280 nm and 530 nm, and that of CNU43 appeared at 430 nm. The relative anthocyanin contents (RAC) per plant of the CU 71 among the new developed rice compared by yield per unit area was very high, fellowed by CNU73 and Heugjinjubyo.

• Journal of Periodontal and Implant Science
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• v.54 no.1
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• pp.13-24
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• 2024

Purpose: This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis. Methods: Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals' hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST). Results: PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results. Conclusions: Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.165-174
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• 1980

The concentrated red ginseng extract (RGE) which was prepared from water extract of red ginseng tails was investigated for its changes in color intensity, sugar contents and during storage at various temperatures. In order to evaluate the color of RCE, a spectrophotometric measurement in ultraviolet and visible range was applied. The concentrated RGE was divided into three fractions of aqueous, butanol and benzene layers. It was found that : (1) Increase in RCE color during heat treatment was considered to be due to nonezymatic browning reaction. Water soluble layer showed approximately 100 times higher color intensity than those of organic solvent layers (2) The RCE stored at 8$0^{\circ}C$ showed an increase in fructose and glucose content while a rapid decrease was resulted at 10$0^{\circ}C$. (3) A rapid increase in absorbances at 400 and 460nm was shown at 90 and 10$0^{\circ}C$ after an initial induction period and slowed down after 50 hours . (4) A significant relationship was found between decrease in sugar content and increase in color intensity. (5) Absorbance ratio of 400nm/460nm indicated that benzene layer has about two times higher value in violet color than those of butanol and aqueous layers.