• Journal of Photoscience
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• v.9 no.2
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• pp.311-313
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• 2002

X-ray structures of pharaonis phoborhodopsin (ppR) show the different direction of the side chain of Arg72 from that of the corresponding residue (Arg82) of bacteriorhodopsin, BR. For BR, this residue is considered to play an important role in the proton pumping. In order to investigate the role of Arg72 in ppR, we constructed Arg72 mutants of R72A, R72K and R72Q, and measured the photocycle and proton pumping activities. The pH-titration curves on the absorption maximum of the mutants were shifted to alkaline in comparison of that of the wild-type. This may imply the increase of pKa of D75, suggesting the presence of the (probably electric) interaction between D75 and Arg72. Rate constants of the M-decay were 3-7 times faster than that of the wild-type, and the time for the completion of the photocycling was also reduced. Using Sn0$_2$ electrode, the rate of transmembrane proton transport was measured upon illumination. The photo-induced proton pumping activities were estimated after the corrections that are the percentages of the associated form of D75 (which has no pumping activity) and the photocycling rates. R72A and R72Q showed the reduced activity while R72K did not reduce the activity.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.487-496
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• 2014

In this study, three kinds of polymers based on phenothiazine-benzothiadiazole were synthesized by a Suzuki coupling reaction, and the various side-chains were substituted at the nitrogen of phenothiazine. The optical and electrochemical properties of synthesized polymers were analyzed. The results indicate that their absorption ranged from 300 to 700 nm, and also confirmed the ideal highest occupied molecular orbital (HOMO) energy level was about -5.4 eV with low band-gap energy. Photovoltaic devices were fabricated using a photoactive layer composed of a blended solution of the polymer and $PC_{71}BM$ in ortho-dichlorobenzene The device with P2HDPZ-bTP-OBT containing the branched side-chain and long chain showed the best performance; the maximum power conversion efficiency of this device was 2.4% (with $V_{OC}$ : 0.74 V, $J_{SC}$ : $6.9mA/cm^2$, FF : 48.0%).

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.712-720
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• 2009

The goal of this study was to elucidate the expression and segmental distribution of the glomerular cationic amino acid metabolism transporter-2 (CAT-2) and thus to improve our understanding of porcine cationic amino acid transporters and amino acid absorption. Porcine CAT-2 was cloned, sequenced and characterized. The predicted amino acid sequence of porcine CAT-2 shared 86.1% and 92.1% identity with human and mouse CAT-2A, respectively. The tissue distribution patterns and ontogenic changes of CAT-2 mRNAs were determined by real-time Q-PCR. The results showed that porcine CAT-2 was highly expressed in the heart and intestinal tract (duodenum, ileum and jejunum). In addition, the mRNA of CAT-2 was found in liver, lung, kidney, brain and muscle. Within the intestinal tract, CAT-2 mRNA was most abundant in the ileum and rarely expressed in the duodenum. In the duodenum, the levels of CAT-2 mRNA reached their peak on day 7 (p<0.05) while in the jejunum, levels were low on day 1 and 7 and increased rapidly after day 26 before peaking on days 30 and 60 (p<0.05). The levels then dramatically decreased by day 90 (p<0.05). In the ileum, levels achieved their maximum on day 30 and then decreased significantly on day 60 (p<0.05).

• Korean Journal of Clinical Pharmacy
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• v.18 no.2
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• pp.106-113
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• 2008

The aim of this study was to evaluate the bioequivalence of two domperidone preparations. Bioequivalence assessment was conducted on 34 healthy volunteers who received two tablets (Domperidone Maleate, 12.72 mg/tablet) in the fasting state, in a randomized balanced $2{\times}2$ cross-over study design. This whole study was performed according to the implementation guidelines of the Korea Food Drug Administration. After dosing of two tablets, blood samples were collected serially for a period of 36 hours. Plasma was analyzed for domperidone by using LC/MS/MS assay method. The analysis system was validated in specificity, accuracy, precision, and linearity. $AUC_t$, (the area under the plasma concentration-time curve from the zero-time to 36 hr) was calculated through the trapezoidal rule. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma domperidone concentration-time data of each volunteer. No significant sequence effect was found for the bioavailability parameters indicating that the cross-over design was properly performed. The 90%-Confidence intervals of the $AUC_t$ ratio and the $C_{max}$ were from log 0.8007 to log 1.1240 and log 0.8645- log 1.2483, respectively. These values were within the acceptable bioequivalence intervals between 0.80 and 1.25. Therefore, this study demonstrated that two formulations have bioequivalence with respect to the rate and extent of absorption.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.70-76
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• 1996

Absorption, distribution, excretion and metabolism of $^{14}C-{\alpha}-Endosulfan$[1,4,5,6,7,7-hexachloro-8,9,10-=trinorborn-5-en 2,3-ylenebismethylene]sulfite) were studied in male mouse(Balb/c) after single intraperitoneal treatment as the dose level of 7.5 mg/kg body weights. After treatment of $^{14}C-{\alpha}-endosulfan$, the radioactivity was rapidly excreted into the urine(63.9 %) within 4 days, thereafter the excretion ratio was constant. Radioactivity levels in the tissues was reached maximum 0.5 hr in heart, 2 hrs in liver and kidney after the treatment, then decreased with time. Endosulfan was metabolized to ${\beta}-endosulfan({\beta}-E)$, endosulfan ether(EE), endosulfan sulfate(ES), and endosulfan alcohol(EA). The main metabolites were EA(13.25 %) in liver and endosulfan hydroxyether(EHE)(19.37 %) in kidney. The urinary metabolites were EA(43.21 %), ES(4.78 %), ${\beta}-E$(7.21 %), EE(3.72 %) and EHE(18.04 %).

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.80-87
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• 2008

This paper investigated into the impact characteristics of the stainless sheet with thickness of 0.7 mm on the stretching boundary condition through three-dimensional finite element analysis. High speed tensile tests were carried out to obtain strain-stress relationships with the effects of the strain rate. The FE analysis was performed by the ABAQUS explicit code. In order to improve an accuracy of the FE analysis, the hyper-elastic model and the damping factor were introduced. Through the comparison of the results of the FE analyses and those of the impact tests, a proper FE model was obtained. The results of the FE analyses showed that the absorption rate of energy maintains almost 82.5-83.5% irrespective of the impact energy level and the diameter of the impact head. From the results of FE analyses, variations of stress, strain, dissipation energy, strain energy density, and local deformation characteristics in the stainless sheet during the collision and the rebound of the impact head were quantitatively examined. In addition, it was shown that the fracture of the specimen occurs when the plastic strain is 0.42 and the maximum value of the plastic dissipation energy of the specimen is nearly 1.83 J.

• Journal of Pharmaceutical Investigation
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• v.38 no.4
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• pp.277-282
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• 2008

The purpose of the present study was to evaluate the bioequivalence of two topiramate tablets, Topamax tablet (Janssen Korea. Co., Ltd., Seoul, Korea, reference drug) and Topamin tablet (Myungmoon Pharm. Co., Ltd., Seoul, Korea, test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four healthy male Korean volunteers received one tablet at the dose of 100 mg topiramate in a $2{\times}2$ crossover study. There were two-weeks washout period between the doses. Plasma concentrations of topiramate were monitored by an LC-MS/MS for over a period of 96 hr after administration. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 96 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance (ANOVA) was carried out using logarithmically transformed $AUC_t$ and $C_{max}$. The 90% confidence intervals of the $AUC_t$, ratio and the $C_{max}$ ratio for Topamin/Topamax were $\log0.88{\sim}\log1.02$ and $\log0.87{\sim}\log1.03$, respectively. These values were within the acceptable bioequivalence intervals of $\log0.80{\sim}\log1.25$. Taken together, our study demonstrated the bioequivalence of Topamax and Topamin with respect to the rate and extent of absorption.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.2
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• pp.191-196
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• 2010

Hybrid heat pumps, which combine the vapor compression and absorption heat pump cycle, can efficiently produce hot water of $80^{\circ}-90^{\circ}C$ from the low temperature of ${\sim}50^{\circ}C$. In this study, the performance of a two-stage hybrid heat pump (HHP) was compared with a single-stage hybrid heat pump using EES (Engineering Equation Solver). For the same operating conditions, the two-stage HHP showed a slightly higher COP (Coefficient Of Performance) and more stable operating conditions than the single-stage HHP. Moreover, the maximum working fluid temperature of the two-stage HHP was found to be lower than that of the single-stage HHP by about 40 K, which makes the working conditions of the lubricating oil safer. The COPs of both systems decreased with increasing UA-values. However, the heat output of the HHP was increased at the same time.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1470-1474
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• 2012

The pharmacokinetics of prunasin after oral administration of amygdalin or a decoction of peach seeds was determined and compared in rats. A $C_{18}$ column was used for separation at a column temperature of $25^{\circ}C$. The mobile phase consisted of 20% aqueous acetonitrile, and the flow rate was 0.5 mL/min. After oral administration of a decoction of peach seeds, prunasin was absorbed rapidly, reaching a maximum plasma concentration ($C_{max}$) of 62.1 mg/L within 45 min. After oral administration of amygdalin, the absorption of prunasin was delayed. The $C_{max}$ of prunasin was 42.9 mg/L and was reached at 60 min. Values for the pharmacokinetic parameters of prunasin, including $T_{max}$, $C_{max}$, AUC, $T_{1/2}$, CL/F, and V1/F, were significantly different for the oral administration of amygdalin compared with that of a decoction of peach seeds.

• Korean Journal of Applied Biomechanics
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• v.21 no.4
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• pp.391-395
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• 2011

To investigate the anticipatory effect on landing patterns during side-cutting maneuver, thirteen healthy female elite college soccer players participated in this study. Three-dimensional knee kinematics, effective mass and correlation between both these were measured and analyzed using a motion analysis and force plates. Each testing session included anticipated tasks, $45^{\circ}$ side-cutting tasks (AC), followed by a set of unexpected side-cutting (UC) in a random order. Knee flexion/extension, valgus/varus and internal/external rotation angles and effect mass were compared by using paired t-test. Also, correlation analysis was performed to identify the relationship between knee angles and effective mass. Effective mass during UC was greater than that during AC. Effective mass and maximum knee flexion angle were positively correlated during AC and not during UC. Based on the relationship between effective mass and knee flexion angle in AC, shock absorption can be controlled by knee joint flexion in pre-predicted movement condition. However, effective mass can not be controlled by knee flexion in UC condition. The unexpected load affects were more irregular on the knee joint, which may be one of the injury mechanisms of anterior cruciate ligament (ACL) in female soccer players.