• Journal of fish pathology
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• v.28 no.1
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• pp.43-51
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• 2015

The pharmacokinetic properties and residue levels of amoxicillin (AMOX) were studied after intramuscular injection to cultured olive flounders ($100{\pm}50g$), Paralichthys olivaceus. For pharmacokinetic studies, AMOX of 20 to 80 mg/kg body weight was administered at $17{\pm}2^{\circ}C$ or $22{\pm}2^{\circ}C$ and AMOX concentrations were determined in plasma, the liver, and the kidney by HPLC-UVD. Plasma samples were assessed at 0.25, 0.5, 1, 3, 6, 12, 24, 48, 72, 96, 168 hours post-dose, whereas liver and kidney concentrations were measured at 0.25 to 48 hours post-dose. The kinetic profiles of AMOX were analyzed by fitting to a 2-compartmental model with PKSolver program. The following parameters were obtained for a single dosage of 20, 40 and 80 mg/kg of body weight at $22^{\circ}C$ and 20 and 40 mg/kg of body weight at $17^{\circ}C$ in plasma, liver and kidney, respectively: $C_{max}$ (the peak concentration)= $27.23-257.36{\mu}g/m{\ell}$, $5.49-41.65{\mu}g/g$, $16.75-129.31{\mu}g/g$; $t_{max}$ (the time for peak concentration)= 0.05-0.91, 1.36-3.28, 1.95-4.49 h. For residue studies, AMOX of 40 and 400mg/kg was administered, and muscle samples were taken at 2, 5, 7, 14 and 21 days post-dose. The residueof AMOX in the muscle were found under the MRLs (maximum residue levels) within 7 days for the two doses.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.2
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• pp.66-73
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• 2017

This study was to evaluate the influential parameters such as intial Cs concentration, reaction temperature, contact time and pH variation of solution on Cs adsorption. Using the experimental data, adsorption kinetics, isotherms and thermodynamic properties were analyzed. The Cs ion adsorption of the zeolite X was effective in the range from pH 5 to 10 and reached equilibrium after 60 minutes. The adsorption kinetics and isotherms of Cs ion with the zeolite X was described well by the pseudo-second-order kinetic and Langmuir isotherm model. The maximum adsorption capacities of Cs ion calculated from Langmuir isotherm model at 293~333 K were from 303.03 mg/g to 333.33 mg/g. It was found that thermodynamic property of Cs ion absorption on the zeolite X was spontaneous and endothermic reaction. The experimental data were fitted a second-order polynomial equation by the multiple regression analysis. The values of the dependent variable calculated by this best fitted model equation were in very good agreement with the experimentally obtained values.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.122-133
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• 1997

Purified diets containing 5 graded levels of threonine were fed to young, growing and finishing pigs to determine the threonine requirement for growth and maintenance. A model was developed to subdivide the threonine requirement for the maintenance from the requirement for growth. From this model, the threonine requirement for growth was 7.733, 10.968 and 11.235 g/kg live weight gain and the maintenance requirement was 0.118, 0.048 and 0.024 g per unit of metabolic body size at each stage of growth, respectively. In the young pigs, the threonine requirement for growth was 0.388 g/g N gain and the maintenance requirement was 0.122 g per unit of metabolic body size. The breakpoint of plasma threonine concentrations was 3.995, 7.933 and 7.738 g/d, respectively. Expected requirements obtained from these formulae were in general agreement with previous estimates. Based on the weight gain vs N gain equation, about 4.24% of the retained protein was comprised of threonine and compared to 3.81%, the mean threonine content of pig muscle CP.

• Journal of Environmental Science International
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• v.24 no.9
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• pp.1145-1153
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• 2015

PVC-Zeolite composite was prepared by immobilizing zeolite with polyvinyl chloride (PVC). The prepared PVC-Zeolite beads were characterized by using X-ray diffractometer (XRD), fourier transform infrared spectrometer (FTIR), thermo gravimetric analyzer (TGA), and scanning electron microscopy (SEM). The removal properties of Sr and Cs ions from aqueous solution were investigated in batch experiment. The removal efficiencies of Sr and Cs ions by the PVC-Zeolite beads were dependent on the initial pH of solution. The removal efficiencies sharply increased at below pH 4 and was kept constant at pH 4 or more. The adsorption kinetics of Sr and Cs ions by the PVC-Zeolite beads were fitted well by the pseudo-second-order model ($r^2$>0.99) more than pseudo-first-order model. The maximum adsorption capacities of Sr and Cs ions calculated from Langmuir isotherm model were 39.37 mg/g and 55.87 mg/g, respectively.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.02a
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• pp.1-11
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• 2004

PAN-4A composite ion exchanger was more selective for Sr ion than other cations and PAN-KCoFC composite ion exchanger has much higher ion exchange capacity for Cs ion than other cations. The ion exchange capacities obtained from Dubinin-Polanyi equation were 3.93 meq/g for Sr ion and 1.50 meq/g for Cs ion using PAN-4A and PAN-KCoFC ion exchangers, respectively. The modified Dubinin-Polanyi model fit the experimental data accurately in multi-component system. The effective surface diffusivities $(D_{s, cff})$ for Sr and Cs ions of PAN-4A and PAN-KCoFC ion exchangers were slightly increased with the different particle sizes.

• Journal of Korean Port Research
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• v.10 no.1
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• pp.15-23
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• 1996

In this paper, the numerical model to analyze the wave absorbing performance of upright perforated plates is developed under the linear potential theory. If the drag force is dominent to the inertia force in passing perforated plate, the characteristics of perforated plates are determined by a nondimensionlized real-value of G or a length scaled real-value of a. The parameters (G,a), which depend on the drag coefficient, porosity and local shape of plates, can be readily obtained by simple experiments. We investigated the reflection coefficients over a wide frequency range according to the arrays of perforated plates with different values of G and a. We found that the wave absorbing system using the arrays of upright perforated plates is sufficient to install in the ocean engineering basin.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1800-1808
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• 2013

Dual-responsive amphiphilic block copolymers were synthesized by combining enzymatic ring-opening polymerization (eROP) of ${\varepsilon}$-caprolactone (CL) and ATRP of N,N-dimethylamino-2-ethyl methacrylate (DMAEMA). The obtained block copolymers were characterized by gel permeation chromatography (GPC), $^1H$ NMR and FTIR-IR. The critical micelle concentration (CMC) of copolymer was determined by fluorescence spectra, it can be found that with hydrophilic block (PDMAEMA) increasing, CMC value of the polymer sample increased accordingly, and the CMC value was 0.012 mg/mL, 0.025 mg/mL and 0.037 mg/mL for $PCL_{50}$-b-$PDMAEMA_{68}$, $PCL_{50}$-b-$PDMAEMA_{89}$, $PCL_{50}$-b-$PDMAEMA_{112}$, $PCL_{50}$-b-$PDMAEMA_{89}$ was chosen as drug carrier to study in vitro release profile of anti-cancer drug (taxol). The temperature and pH dependence of the values of hydrodynamic diameter (Dh) of micelles, and self-assembly of the resulting block copolymers in water were evaluated by dynamic light scattering (DLS). The result showed that with the temperature increasing and pH decreasing, the Dh decreased. Drug-loaded nanoparticles were fabricated using paclitaxel as model. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) had been explored to study the morphology of the hollow micelles and the nanoparticles, revealing well-dispersed spheres with the average diameters both around 80 nm. In vitro release kinetics of paclitaxel from the nanoparticles was also investigated in different conditions (pH and temperature, etc.), revealing that the drug release was triggered by temperature changes upon the lower critical solution temperature (LCST) at pH 7.4, and at $37^{\circ}C$ by an increase of pH.

• Environmental Engineering Research
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• v.25 no.3
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• pp.426-438
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• 2020

In this study, cherry kernel shell pyrolytic charcoal was synthesized (CKSC) and composite beads were obtained by blending this pyrolytic charcoal with chitosan and Fe₂O₃ nanoparticles (Fe-C-CKSC). Cr(VI) adsorption from aqueous solutions by Fe-C-CKSC composite beads and CKSC adsorbents was studied comparatively. The effects of Cr(VI) initial concentration, adsorbent dosage, contact time, pH and temperature parameters on Cr(VI) adsorption were investigated. Adsorption reached an equilibrium point within 120 min for CKSC and Fe-C-CKSC adsorbents. The maximum Cr(VI) removal was obtained at the initial pH value of 1.56 for CKSC and 2.00 for Fe-C-CKSC. The optimum adsorbent dosage was found to be 5 g/L for CKSC and 3 g/L for Fe-C-CKSC. Based on the Langmuir model, the maximum adsorption capacities were calculated as 14.455 mg/g and 47.576 mg/g for CKSC and Fe-C-CKSC, respectively. Thermodynamic and kinetic studies were performed. As a result of adsorption kinetics calculations, adsorption was found to be consistent with the pseudo second order kinetic model. Characterization of the synthesized adsorbents was performed by SEM, BET, FTIR and elemental analysis. This study has shown that low cost adsorbents CKSC and Fe-C-CKSC can be used in Cr(VI) removal from aqueous solutions.

• YAKHAK HOEJI
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• v.54 no.1
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• pp.55-61
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• 2010

Gardenia jasminoides is one of the most widely used herbal preparations for the treatment of liver disorders. This study evaluated the potential beneficial effect of G. jasminoides in a mouse model of carbon tetrachloride ($CCl_4$)-induced liver injury. The mice were treated intraperitoneally with $CCl_4$ (10 ${\mu}l$/kg). They received G. jasminoides (30, 100, 300 mg/kg) 48 h, 24 h and 2 h before and 6 h after administering $CCl_4$. The serum activities of aminotransferase and the hepatic level of malondialdehyde were significantly higher 24 h after the $CCl_4$ treatment, while the concentration of reduced glutathione was lower. These changes were attenuated by G. jasminoides. $CCl_4$ increased the level of circulating tumor necrosis factor-$\alpha$ (TNF-$\alpha$) markedly, which was reduced by G. jasminoides. The levels of hepatic inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression were markedly higher after the $CCl_4$ treatment. G. jasminoides diminished these alterations. $CCl_4$ increased the level of TNF-$\alpha$, iNOS and COX-2 mRNA expressions, and these increases were attenuated by G. jasminoides. These results suggest that G. jasminoides alleviates $CCl_4$-induced liver injury, and this protection is likely due to the reduced oxidative stress and the downregulation of proinflammatory mediators.

• Journal of Korean Neurosurgical Society
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• v.63 no.6
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• pp.707-716
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• 2020

Objective : The function of B7H3, a member of the B7 family of proteins, in neuroblastoma (NB) remains poorly characterized. Here we examine the expression pattern of B7H3 in clinical NB specimens and characterize the phenotype of B7H3 knock-down in NB cell line. Methods : Immunohistochemical (IHC) staining was carried out to assess the expression of B7H3 in clinical NB specimens. Survival association was analyzed using five Gene Expression Omnibus (GEO) datasets (GSE85047, GSE45480, GSE62564, GSE16476, GSE49710). Clonogenic survival and flow cytometry were performed after B7H3 knockdown to assess the cellular proliferation and cell survival in vitro. Impact of B7H3 silencing on NB growth was examined in vivo using the SH-SY5Y xenograft model. Results : On IHC staining, B7H3 was widely expressed in clinical NB specimens. Analysis of the transcriptional profiles of five GEO datasets clinically annotated NB specimens revealed that decreased B7H3 expression was associated with improved overall survival. B7H3 knockdown suppressed the proliferation of the SH-SY5Y NB model in vitro and in vivo. Cell cycle analysis revealed that B7H3 silencing induced G1/S arrest. This arrest was associated with the suppression of E2F1 expression and induction of Rb expression. Conclusion : Our results demonstrate that B7H3 expression correlate with clinical survival in NB patients. Preliminary studies suggest that B7H3 may mediate the G1/S transition.