• Korean Journal of Materials Research
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• v.11 no.7
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• pp.550-555
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• 2001

A diamond-like carbon(DLC) films were deposited on the borosilicate glass substrate by radio frequency plasma enhanced chemical deposition(rf-PECVD). The $methane(CH_4)-hydrogen(H_2)$ gas mixture was used as precursor gas. The morphologies, the structure and the optical properties of the DLC films were investigated by SEM, Raman and UV spectrometer. The deposition rate was slightly increased with the hydrogen concentration in the gas mixture and it maintained constant at over 25 sccm of the gas flow rate. The optical band gap calculated by UV spectra decreased with increase of deposition time and DC self bias, but that were not effected by hydrogen content. Most effective parameter on the transmittance of film was bias voltage, especially in the range of ultra violet and visible light.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.42-46
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• 2010

This study was performed to investigate anti-wrinkle effects of Acanthopanax senticosus (AS) on ultraviolet B (UVB)-induced photoaging with wrinkle formation. AS extract showed higher DPPH radical scavenging activity (3 ${\mu}g/mL$ as $IC_{50}$) and collagenase inhibition (1.52 mg/mL as $IC_{50}$) than those of ascorbic acid (50 ${\mu}g/mL$ and 2.17 mg/mL, respectively). Cell proliferation and type I pN collagen synthesis were increased by 11.4% and 96.4%, respectively, compared with non treatment control. In vivo, SKH-1 hairless mice were administrated AS 400 mg/kg for 10 weeks with UVB irradiation three times a week. After 10 weeks, a visual assessment and replica assay were performed on each mouse. According to visual assessment of close-up photos and skin replica, oral administration of A. senticosus affected on inhibition of wrinkle formation caused by UVB irradiation on the skin of mice as compared to the vehicle treated control mice. These results indicated that A. senticosus could protect skin wrinkle formation caused by collagen synthesis of fibroblast cells and photo-irradiation of UVB in hairless mice.

• Atmosphere
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• v.27 no.3
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• pp.291-300
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• 2017

The monthly-mean irradiance of ultra violet (UV)-B and UV-A observed from 2005 to 2014 and 2012 to 2014, respectively, at noon in Gosan, Jeju, South Korea are analyzed. We compare cloudiness, total ozone, visibility, and relative humidity with an emphasis on the four months from May to August (MJJA), which shows the largest UV radiation. While the incoming UV-B radiation at the top of the atmosphere in Gosan is the largest in June due to the small solar zenith angle, the observed surface UV-B shows an unexpected smaller value in June than those in May, July or August. In June, the meteorological conditions affecting Gosan are completely dominated by cloudiness and thus, frequent overcast seems to determine the minimum UV-B. Another important UV-determining factor is the total ozone, which exhibits a monotonic decrease during MJJA without agreeing to the characteristic feature of UV. The ratio of UV-B to UV-A is not generally influenced by cloudiness. Thus, the ratio is a useful indicator of atmospheric turbidity showing larger values for increasing visibility, except in June. A simple model has been used to estimate surface UV by using the observed ozone and visibility in the cloudless condition. The result shows that UV has the lowest value in June with small variation during MJJA. Model estimation also shows that the different characteristic features observed in July between surface UV-B and UV-A is the result of less absorption of UV-B by ozone than that of UV-A by a smaller amount of total ozone.

• The Journal of Korean Physical Therapy
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• v.18 no.3
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• pp.79-87
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• 2006

Purpose: The present study purposed to examine induced characteristic or erythema and safety by medium wave ultra violet(UVB) lamp. Methods: We compared sunshine and UVB lamp using spectroradiometer and UV radiometer. For measuring sunshine irradiation, we used spectoradiometer and detected from 8 to 18 o'clock every each hour on the beach, playground and rooftop of a 5 story building. The subjects for erythema examination were 5 healthy subjects who have no pathologic history of photosensitivity reaction, psoriasis and vitiligo. They were exposed to UVB radiation at the abdominal area for 2 hours and after irradiation, we observed the change of skin color every 12 hours over a period of 1 week. Results: Between sunshine and UVB lamp, sunshine had higher data on the chromaticity coordinates, dominant and peak wavelength, bandwidth and purity than the UVB lamp but on the color temperature, brightness the UVB lamp had higher data than the sunshine. In comparison of sunshine and UVB lamp, UVB lamp irradiated constantly such as $3.9-4.4{\mu}W/cm^2$ at a distance of 100cm between bed and lamp which was same as early morning irradiation on the sunshine. The erythema didn't appear to any subject. Conclusion: This results suggest that the UVB lamp has lower irradiance as much as early sunshine. Therefore the UVB lamp had no influence of inducing erythema at a distance of 100cm between bed and lamp.

• Biomolecules & Therapeutics
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• v.15 no.2
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• pp.118-122
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• 2007

This study was performed to evaluate the bioequivalency between the Osmetone$^{TM}$ Tablet (Myeongmoon Pharm. Co., Ltd.) as a test formulation and the Relafen$^{TM}$ Tablet (Handok Pharm. Co., Ltd.) as a reference formulation. Twenty-four healthy male volunteers were administered the formulations by the randomized Latin square crossover design, and the plasma samples were determined by a high performance liquid chromatography (HPLC) with Ultra-Violet (UV) detector. AUC$_t$, C$_{max}$ and T$_{max}$ were obtained from the time-plasma concentration curves, and log-transformed AUC$_t$ and C$_{max}$ and log-untransformed T$_{max}$ values for two formulations were compared by statistical tests and analysis of variation. AUC$_t$ was determined to be 897.8${\pm}$431.1 ug.hr/ml for the reference formulation and 902.3${\pm}$408.4 ug.hr/ml for the test formulation. The mean values of C$_{max}$ for the reference and test formulations were 24.2${\pm}$8.9 and 24.0${\pm}$9.5 ug/ml, respectively. The AUC$_t$ and C$_{max}$ ratios of the reference Relafen$^{TM}$ Tablet to the test Osmetone$^{TM}$ Tablet were +5.01% and -0.83%, respectively, showing that the mean differences were satisfied the acceptance criteria within 20%. The results from analysis of variance for logtransformed AUC$_t$ and C$_{max}$ indicated that sequence effects between groups were not exerted and 90% confidence limits of the mean differences for AUC$_t$ and C$_{max}$ were located in ranges from log 0.80 to log 1.25, satisfying the acceptance criteria of the KFDA bioequivalence. The Osmetone$^{TM}$ Tablet as the test formulation was considered to be bioequivalant to the Relafen$^{TM}$ Tablet used as its reference formulation, based on AUC$_t$ and C$_{max}$ values.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.506-506
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• 2013

Ag (Silver) 박막은 낮은 전기 저항과 높은 가시광대의 반사율을 가져 T-OLED (Top Emission-Organic Light Emitting Diode)의 Anode로 각광 받고 있지만, 일반적인 Ag 박막의 일함수는 4.3 eV 이하로 T-OLED의 Anode로 사용하기에는 낮은 단점이 있다. 따라서 이를 극복하기 위한 방법으로 Ag 박막 표면을 산화시켜 일함수를 증가시키기 위한 연구가 진행중에 있다. 하지만 연구는 단순히 일함수를 증가시키는 것에 한정되어 있을 뿐 UV 처리된 박막의 nano-mechanics 특성에 대한 연구는 현재 전무하다. 따라서 본 연구에서는 순도 99.9%의 Ag 타겟을 이용하여 rf magnetron sputter 장비를 통해 Ag 박막을 증착 하였고, 이후 UV (Ultra-Violet) 램프를 통해 시료 표면을 산화시켰다. 특히, 이 논문의 주요 관심사인 박막의 nano mechanics 특성 분석을 위하여 nano indenter와 SPM (Scanning Probe microscope) 장치를 활용 하였다. 실험 결과 후처리 시간이 3분 이하인 경우 박막이 비결정질의 silver oxide로 성장하는 것을 확인하였으며, 이때 박막의 면저항은 $0.16{\Omega}$/sq.에서 $0.55{\Omega}$/sq.로 증가하는 것을 관찰할 수 있었고, 3분 이후, 비결정질의 silver oxide가 conducting 특성을 갖는 silver oxide 결정을 이루면서 면저항이 $0.55{\Omega}$/sq.에서 $0.21{\Omega}$/sq.로 감소하는 것을 보았다. 또한 결정질의 박막이 자라는 3분이상의 박막에서 surface hardness는 급격하게 증가($3.57{\rightarrow}9.47$ GPa)했으며, 6분 이후에는 감소하는($9.47{\rightarrow}3.46$ GPa) 경향을 보였다. 이러한 경향은 silver oxide의 결정 크기가 Ag 결정 보다 크므로 상대적인 압축응력을 받아 표면 경도가 증가됐다. 처리시간 6분 이후, 경도 감소는 박막의 표면 물성이 불안정해졌기 때문이다.

• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.41-49
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• 1985

Bacillus sphaericus was mutagenized with UV light irradiation and dimethyl sulfate. Thirty-five conditional lethal temperature-sensitive(ts) mutants were isolated at the nonpermissive temperature of $42^{\circ}C$ and classified into three groups by their growth characteristics on the nutrient broth, peptone glucose yeast extract agar and mineral salts agar. First was the lethal ts group, 24 mutants, which did not grow at the nonpermissive temperature, the second, 9 mutants, was the less growth is group whose growth was restricted to one-half, and the third, 2 mutants, was the cold lethal ts group whose growth was restricted at the permissive temperature($25^{\circ}C$and $30^{\circ}C$)

• Journal of Pharmaceutical Investigation
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• v.35 no.5
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• pp.355-360
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• 2005

The purpose of the present study was to evaluate the bioequivalence of two cetirizine HCl tablets, Zyrtec tablet (UCB Pharm. Co., Ltd. Korea, reference product) and Zyrix tablet (Kukje Pharm. Co., Ltd., Korea, test product), according to the guidelines of Korea Food and Drug Administration (KFDA). After adding an internal standard (diazepam), plasma samples were extracted using 1 mL of dichloromethane. Compounds extracted were analyzed by reverse-phase HPLC with ultra-violet detector. This method for determination cetirizine is proved accurate and reproducible with a limit of quantitation of 10 ng/mL in male plasma. Twenty-four healthy male Korean volunteers received each medicine at the cetirizine HCl dose of 10 mg in a $2{\times}2$ crossover study. There was a one-week wash out period between the doses. Plasma concentrations of cetirizine were monitored for over a period of 24 hr after the administration. AUC (the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters indicating that the crossover design was properly performed. The 90% confidence intervals for the log transformed data were acceptable range of log 0.8 to log 1.25 $(e.g.,\;log\;0.93-log\;1.08\;for\;AUC_{0-t},\;log\;0.91-log\;1.08\;for\;AUC_{0-{\infty}}\;and\;log\;1.01-log\;1.11\;for\;C_{max})$. The major parameters, AUC and $C_{max}$ met the criteria of KFDA for bioequivalence indicating that Zyrix tablet is bioequivalent to Zyrtec tablet.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.39-45
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• 1983

One of Streptomyces sp. was screened as an antibiotic producing strain against Gram positive bacteria specifically from about one hundred Actinomycetes collections. The isolated KM-48 strain, indexed in our collection, was secreted an anbitiotic in nutrient broth culture. The active principle was extracted with acetone from the lyophilized solid of cultured filtrate. The nonadsorbed elute in aluminium oxide was isolated as a purified homogeneity which revealed a sing1e spot under ultra-violet beam on avicel thin layer chromatography. The isolated antibiotic was sensitive specifically against the Gram positive bacteria and fungi. About fifty percent inhibition of the control growth on Bacillus amyloliquefaciens was 18$\mu\textrm{g}$/$m\ell$. The antibiotic was lavile against thermotreatment and stabled in acidic condition remarkably. The KM-48 was identified as a similar strain to Streptomyces tsusimaensis on its morphological and cultural characteristics.

• Journal of the Korean Applied Science and Technology
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• v.24 no.3
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• pp.238-245
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• 2007

$Eu^{3+}$ doped $YGdO_3$ phosphors particles which have fine size and narrow size distribution with non aggregated uniform morphology were prepared by solvent evaporation method for the improvement of emission efficiency. Several parameters have been investigated in this study such as the influences of composition ratio of host materials, calcination temperature, amount of activator, surfactant, pH and flux on the photoluminescence intensity, particle size and dispersion. $Eu^{3+}$ doped $YGdO_3$ phosphor presented a strong narrow band emission peak at 612nm. The maximum emission intensity of$YGdO_3:Eu^{3+}$ occurred when $Eu^{3+}$ concentration is 3wt% under vacuum ultra violet excitation. Prepared phosphors were found to have small round-shaped particles about 150nm in size. The addition of PVA as a surfactant inhibits the grain growth and the agglomeration of particles efficiently by reducing the oxygen bridge bonds. As the pH reduces, PL intensity increase due to reducing the formation of oxygen bridge bonds. The particles prepared from solvent evaporation method with 5wt% LiCl were found to have 120% PL intensity compare to particles prepared without LiCl flux.