• Journal of Korean society of Dental Hygiene
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• v.12 no.1
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• pp.81-91
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• 2012

Objectives : By investigating antimicrobial activity of natural extracts, identifying its usefulness as antibiotic material to oral bacteria. Methods : Antimicrobial activity tests of 25 natural extracts were implemented on 6 type strains alleged to cause dental caries and 10 clinical strains isolated and identified from dental caries. Results : Among medicinal plants, Coptis japonica, Scutellaria baicalensis, Dictamnus dasycarpus showed antimicrobial activity. Among lichens, 3 methanol extracts and 6 acetone extracts showed antimicrobial activity. Minimum Inhibitory Concentration(MIC) test of Usnea aurantiacoatra KoLRI 004184, an acetone extract of lichen with the highest antimicrobial activity, on 6 type strains involved in dental caries and 10 strains isolated from dental caries resulted as follows; Actinomyces oris 1041 $12{\mu}g/ml$, for Corynebacterium durum 3151 $13{\mu}g/ml$, for Rothia dentocariosa KCTC $3204^T$ $14{\mu}g/ml$, for R. dentocariosa 911 $15{\mu}g/ml$, for R. dentocariosa 1822 $12{\mu}g/ml$, for Lacto-bacillus casei KACC $12413^T$ $12{\mu}g/ml$, for L. acidophilus KACC $12419^T$ $16{\mu}g/ml$, for L. rhamnosus 2421 $15{\mu}g/ml$, for Streptococcus mutans KCTC $3065^T$ $15{\mu}g/ml$, for S. mutans 121 $13{\mu}g/ml$, for Streptococcus oralis 2221 $18{\mu}g/ml$, for S. salivarius KCTC 5512 $14{\mu}g/ml$, for S. salivarius 122 $12{\mu}g/ml$, for S. sanguinis KCTC $3284^T$ $14{\mu}g/ml$, for S. sanguinis 912 $14{\mu}g/ml$, for Neisseria sp. KEM232 $12{\mu}g/ml$. Conclusions : Even a small amount of extract from lichen Usnea aurantiacoatra KoLRI 004184 showed very high level of antimicrobial activation against all 16 bacterial strains involved in dental caries.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.592-598
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• 1985

The total vibrational deexcitation rate constants $k_{v,v-1}$ of HF(v = 5-7) by HF(${\mu}$ = 0) and DF(${\mu}$ = 9-12) by DF(${\mu}$= 0) including both the vibration to vibration (V ${\to}$ V) and vibration to rotation and translation (V ${\to}$ R, T) energy transfer channels have been calculated semiclas-sically using a simplified collision model. The calculated results are in reasonably good agreement with those obtained by experimental and other theoretical studies. The rate constants increase with increasing temperature and also with increasing v. They also show that the relaxation of the highly excited HF and DF occurs predominantly via the V ${\to}$ R, T path at low temperature. The effectiveness of the V ${\to}$ V path, however, increases as the temperature is raised.

• Development and Reproduction
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• v.12 no.3
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• pp.261-266
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• 2008

In the present study, we investigated in vivo effects of Manchurian trout recombinant gonadotrophin hormone (mt-rGTH) on the induction of maturation in female eel, Anguilla japonica. The brood stock, female eel (450$\pm$50 g) were weekly injected intramuscularly with different doses of 0.1, 1, 10 ${\mu}g\m{\ell}$/fish (mt-rFSH or mt-rLH) for 10 week. The effects of r-mtGTH were analyzed by gonadosomatic index (GSI), ovarian follicle diameter and sex steroid levels. All groups did not exhibit significant differences in the GSI values. Whereas plasma testosterone (T) and estradiol-17$\beta$ (E2) levels did not change significantly in control group, plasma levels of T and E2 by injection of the r-mtFSH or r-mtLH were increased at 2 or 4 week after injection. In addition, injection of the mt-rFSH (1, 10 ${\mu}g/m{\ell}$/fish) or mt-rLH (0.1, 1, 10 ${\mu}g/m{\ell}$/fish) significantly increased follicle diameters comparing to the control group. These results demonstrate that the recombinant hormone may affect early ovary development and maturation in female eel. Taken together, these results suggest that the recombinant Manchurian trout FSH and LH are effective for reproductive activities in female eel.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.200-205
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• 2002

Temperature-dependent pharmacokinetics of ciprofloxacin (CIP) was studied in the cultured olive flounders, Paralichthys olivaceus, and black rockfish, Sebastes schlegeli using high performance liquid chromatography (HPLC) originally developed for quinolone determination from livestock. Pharmacokinetics of CIP was apparently affected by ambient water temperature. In a two-compartment model for flounders after oral dosage of 20 mg/kg, $K_{01},\;at\;13^{\circ}C$ and $23^{\circ}C$ were 4.18 and 1.20/hr, respectively. The $K_{10},\;T_{max}\;and\;C_{max}\;at\;13^{\circ}C$ were 5.574/hr, l4.37${\mu}g/mL\;and\;3.15{\mu}g/mL,$ respectively. The corresponding values at $23^{\circ}C$ were l2.84/hr, 15.39${\mu}g/mL\;and\;6.38{\mu}g/mL$, respectively. The AUC, $T_{1/2} (\alpha)\;and\;T_{1/2}\;(\beta)$ were 278.23 ${\mu}g \cdot hr/mL$, 0.24hr and 47.02hr at $13^{\circ}C$ and 3l7.8l${\mu}g \cdot hr/mL$, 0.30 hrs and 60.78hrs at $23^{\circ}C$ for the flounder, respectively. Similar CIP pharmacokinetics were revealed in the black rockfish after oral dosage of 20 mg/kg under the two water temperature regimes. These pharmacokinetical results have some implication in the optimal usage of recently introduced antibacterials in the farmed fish, which were primarily adapted for poultry and mammalian species.

• Journal of the Korean Applied Science and Technology
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• v.28 no.1
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• pp.64-74
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• 2011

The aim of study was to investigate polluted amounts 16 PAHs in railroad(waste railway ties) area, factory area and land-fill area. All of the samples were analyzed by GC-MSD(SIM mode), and the recovery range, detection limit and standard deviation obtained by this experiment were 73.88 ~ 94.75%, 0.009 ~ 2.252 ${\mu}g$/kg and 1.861 ~ 12.373, respectively. The concentrations of total PAHs(t-PAHs) and total carcinogenic PAHs(t-PAHcarc) in soils of three area were in the range of 12.54 ~ 3274.95 ${\mu}g$/kg on a wet weight basis with a mean value of 499.8 ${\mu}g$/kg and 0 ~122.77 ${\mu}g$/kg with a mean value of 20.16 ${\mu}g$/kg, respectively. The correlation between t-PAHs and t-PAHcarc appeared very high in railroad(waste railway ties) area ($R^2$ = 0.8301), factory area ($R^2$ = 0.9217) except land-fill area($R^2$ = 0.3782), indicated that t-PAHcarc concentration increases in proportion with t-PAHs.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.1
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• pp.1-8
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• 2015

To evaluate accuracy and precision of determination of total alkalinity ($Alk_T$) and carbon dioxide ($TCO_2$) derived from present study, experiment was applied with $CO_2$ CRM (Batch 132, Scripps Institution of Oceanography; $Alk_T=2229.24{\pm}0.39{\mu}mol/kg$, $TCO_2=2032.65{\pm}0.45{\mu}mol/kg$). As the result, average concentration of $Alk_T$ and $TCO_2$ was $2354.09{\mu}mol/kg$ (~5.6% difference with $CO_2$ CRM) and $2089.60{\mu}mol/kg$ (~2.3% difference with $CO_2$ CRM), respectively. For previous method (Gran Titration) by addition $NaHCO_3$ to deionized water($Alk_T$ $2023.33{\mu}mol/kg$), average concentration was $2193.39{\mu}mol/kg$ (sd=57.15, n=7). Whereas, average concentration was $2017.02{\mu}mol/kg$ (sd=10.98, n=7) for the present study. Recovery yield experiments of total alkalinity in deionized water and seawater were implemented by addition of $NaHCO_3$. The recovery yield of deionized water in the range 0 to $4952.39{\mu}mol/kg$ was 100.8% ($R^2$=0.999), and seawater in the range 0 to $2041.32{\mu}mol/kg$ was 102.3% ($R^2$=0.999). Comparison of $pCO_2$ sensor (PSI $CO_2-Pro^{TM}$) with present method showed very meaningful correlation coefficient ($R^2$=0.977) in the range of 427 to $705{\mu}atm$ and 9.16 to $15.24{\mu}mol/kg$ throught elapsed time for two weeks. Field experiment of diurnal variation of total carbon dioxide was accomplished at Sachon harbor in the coastal waters of East Sea of Korea. Concentration of $Alk_T$ and $TCO_2$ was increased during night, and decreased during daylight hours. The results showed mirror type between $TCO_2$ and dissolved oxygen, which was attributable to photosynthesis and respiration of phytoplankton. Also, open ocean field study was performed to obtain vertical profile of $Alk_T$ and $TCO_2$ in C-C zone (Clarion-Clipperton Fracture Zone), Northeastern Pacific. Average concentrations of $Alk_T$ in the surface mixed layer (0~60 m) and deeper layer below 200 m were $2422.38{\mu}mol/kg$ (sd=78.73, n=20) and $2465.87{\mu}mol/kg$ (sd=57.68, n=103), respectively. And average concentrations of $TCO_2$ were $2134.47{\mu}mol/kg$ (sd=65.4, n=20) and $2431.87{\mu}mol/kg$ (sd=65.02, n=103) in the same depth ranges such as $Alk_T$. Vertical distributions of $Alk_T$ and $TCO_2$ concentrations tended to increase with depth, and analyzed concentrations showed slightly higher than those of previous studies in this area.

• Journal of applied mathematics & informatics
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• v.30 no.1_2
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• pp.161-171
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• 2012

We consider the fourth-order differential equation with one-dimensional $p$-Laplacian (${\phi}_p(x^{\prime\prime}(t)))^{\prime\prime}=f(t,x(t),x^{\prime}(t),x^{\prime\prime}(t)$) a.e. $t{\in}[0,1]$, subject to the boundary conditions $x^{\prime\prime}}(0)=0$, $({\phi}_p(x^{\prime\prime}(t)))^{\prime}{\mid}_{t=0}=0$, $x(0)={\sum}_{i=1}^n{\mu}_ix({\xi}_i)$, $x(t)=x(1-t)$, $t{\in}[0,1]$, where ${\phi}_p(s)={\mid}s{\mid}^{p-2}s$, $p$ > 1, 0 < ${\xi}_1$ < ${\xi}_2$ < ${\cdots}$ < ${\xi}_n$ < $\frac{1}{2}$, ${\mu}_i{\in}\mathbb{R}$, $i=1$, 2, ${\cdots}$, $n$, ${\sum}_{i=1}^n{\mu}_i=1$ and $f:[0,1]{\times}\mathbb{R}^3{\rightarrow}\mathbb{R}$ is a $L^1$-Carath$\acute{e}$odory function with $f(t,u,v,w)=f(1-t,u,-v,w)$ for $(t,u,v,w){\in}[0,1]{\times}\mathbb{R}^3$. We obtain the existence of at least one nonconstant symmetric solution by applying an extension of Mawhin's continuation theorem due to Ge. Furthermore, an example is given to illustrate the results.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.94-97
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• 2003

This study performed the research about the recycling basin supernatant by pre-coat filtration in the D water treatment plant at Gwangju. Choice the prompt conditions with diatomaceous earth filtration which makes contaminant reduced in the basin supernatant. Element disk of candle used in this experiment are pore size 10$\mu\textrm{m}$(R), 20$\mu\textrm{m}$(B) and 40$\mu\textrm{m}$(Y). Diatomaceous earth are cake pore size 3.5$\mu\textrm{m}$(A), 7$\mu\textrm{m}$(B) and 17$\mu\textrm{m}$(C). The filtrate concentrations were from 0.18 to 0.92$\mu\textrm{g}$/1 of Chlorophyll-a. And then, removal rate percentage were from 78.30 to 95.57(R-A). In addition SS 80%, CODMn32% COD 61%, T-N 10% and T-P 39% on the D water treatment plant. The R(40$\mu\textrm{m}$) C(17$\mu\textrm{m}$) process can be substituted of reusing the recycled water of recycling basin supernatant view of capacity and removal rate of filtrate.

• ETRI Journal
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• v.30 no.4
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• pp.526-534
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• 2008

This paper presents a fully integrated 0.13 ${\mu}m$ CMOS MB-OFDM UWB transmitter chain (mode 1). The proposed transmitter consists of a low-pass filter, a variable gain amplifier, a voltage-to-current converter, an I/Q up-mixer, a differential-to-single-ended converter, a driver amplifier, and a transmit/receive (T/R) switch. The proposed T/R switch shows an insertion loss of less than 1.5 dB and a Tx/Rx port isolation of more than 27 dB over a 3 GHz to 5 GHz frequency range. All RF/analog circuits have been designed to achieve high linearity and wide bandwidth. The proposed transmitter is implemented using IBM 0.13 ${\mu}m$ CMOS technology. The fabricated transmitter shows a -3 dB bandwidth of 550 MHz at each sub-band center frequency with gain flatness less than 1.5 dB. It also shows a power gain of 0.5 dB, a maximum output power level of 0 dBm, and output IP3 of +9.3 dBm. It consumes a total of 54 mA from a 1.5 V supply.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.3
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• pp.225-236
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• 2012

In this study, the cellular protective effects on HaCaT cells and human erythrocytes and antioxidative effects of P. tricuspidata stem extracts were investigated. The ethyl acetate ($50{\mu}g/mL$) and aglycone fraction ($25{\mu}g/mL$) of P. tricuspidata stem extracts doesn't show any characteristics of cytotoxicity. When HaCaT cells were treated with 10 mM $H_2O_2$ and $30{\mu}M$ rose bengal, the ethyl acetate ($6.25{\sim}50{\mu}g/mL$) and aglycone ($6.25{\sim}25{\mu}g/mL$) fraction protected the cells against the oxidative damage in a concentration dependent manner. The P. tricuspidata stem extracts showed more prominent cellular protective effect than (+)-${\alpha}$-tocopherol, known as lipid antioxidant at $10{\mu}g/mL$. The ethylacetate fraction of P. tricuspidata stem extracts ($18.5{\mu}g/mL$) showed more free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC5_{50}$). Reactive oxygen species (ROS) scavenging activity ($OSC_{50}$) of P. tricuspidata stem extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system was investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate ($1.72{\mu}g/mL$) and the aglycone fraction ($1.53{\mu}g/mL$) showed similar ROS scavenging activity of L-ascorbic acid ($1.50{\mu}g/mL$). These results indicate that extract/fractions of P. tricuspidata stem extracts can function as natural cytoprotective agents and antioxidants in biological systems, particularly skin exposed to UV radiation by protecting cellular membrane against ROS.