• Parasites, Hosts and Diseases
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• v.26 no.2
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• pp.73-86
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• 1988

The sensitivity and specificity of crude and affinity-purified antigens of Clcnorchis sinensis obtained from the infected rabbits were studied. Stage-specific antigenic proteins from the eggs, metacercariae and adult worms were characterized by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent astray (ELISA). The results were as follows: 1. The antibody.binding antigen (ABA) purified from whole worm crude antigen (IVWA) by CNBr-activated Sepharose 4B affinity chromatography made :l specific bands against rabbit antisera on Ouchterlony gel diffusion plate, while WWA made 7 bands. Major WWA protein bands by SDS-PAGE were found at 16, 300~18, 500 and 28, 000~29, 000 daltons, while major ABA protein bands were at 18, 000~21, 000 and 29, 000~31, 000 daltons. The reactivity of ABA with rabbit anti-sera in ELISA was remarkably less sensitive than that of WWA. 2. Molecular weights of egg antigen (EGA), metacercarial antigen (MEA) and adult worm antigen (WWA) of C. sinensis ranged from 15, 000-200, 000 daltons, 15, 000-100, 000 daltons and 11, 000~80, 000 daltons, respectively. Major WWA proteins consisted mainly of polypeptide bands of low molecular weight, less than 31, 000 daltons, while those of EGA and MEA consisted of higher molecular T.eights than 30, 000 daltons. 3. The ELISA reactivities of WWA to rabbit anti.sera were remarkably greater than those of MEA. EGA showed negative reaction throughout the experiments. WWA showed higher optical density (O.D.) than 1.0, when reacted with rabbit anti-sera obtained at 4~6 weeks after the infection. In the rabbit anti-sera later than 12 weeks after the infection, the O.D. reacting witll WWA showed a plateau without variation. MEA shoT.ed relatively low O.D. values (<0.6), when reacted with anti-sera from lightly in(ected groups throughout the experiments, althougll there were some wealth positive cases (O.D.>0.6) ill heavily infected groups. MEA reacted with rabbit anti-sera showed negative results on Ouchterlony gel diffusion plates. Summarizing the above results, it is suggested that the whole worm antigen prepared from the adult worms of C. sinensis is most highly antigenic. However, this antigen might reveal cross reactions with other trematodes such as Paragonimus westermani, therefore, purification of antigenic proteins from the crude antigen is essential 18 increase the sensitivity and specificity for the immuncdiagnosis of clonorchiasis.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.50-55
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• 2002

Biological control against mushroom fly, Lycoriella mali, was performed by using Bacillus thuringiensis subsp. israelensis Bti-D and Bti-U, isolated from dead mushroom fly in oyster mushroom houses. Control values of the bacterial strains Bti-D and Bti-U against L. mali in bottle culture of oyster mushroom were 74.4% and 64.2%, respectively, and the value in small tray culture were 75.8% and 56.8%, respectively. In the experiment to develop the mass, cheap media for Bti-D and Bti-U isolates, the Biji broth (bean curd residue, called Biji in Korean language) was selected as a culture medium for an inexpensive and mass cultivation by the measurement of optical density of the two bacteria grown in the different media tested. Insecticidal effect of the formulation contained different ingredients that were prepared by using the Bti-D strain cultured in the Biji broth was tested in tray and bottle culture of oyster mushroom. The WCS formulation that contained corn starch as bio-gel (86.4%) was more effective to control the mushroom fly than living cells (69.1%) in bottle culture of oyster mushroom. Moreover, insecticidal effect of the WCS formulation was improved when water of pH 8 was used for dilution of the formulation. Effect of the WCS formulation using water of pH 8 and chemicals, Zuron (dimillin) W.P. on the control of mushroom fly and the productivity of oyster mushroom was investigated in tray culture of oyster mushroom. The Zuron W.P. was more effective to control the mushroom fly than the WCS formulation. However, compared with no treatment, the productivity of the mushroom treated with the WCS formulation was improved than that of the mushroom with Zuron W.P.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.118-126
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• 1986

Vibrio vulnificus is a recently recognized halophilic organism that nay cause serious human infections. Patients infected with V. vulnificus often have a history of exposure to the sea, suggesting that the organism may be common inhabitant of marine environment. The purpose of this experiment is to investigate the distribution and bacteriological characteristics of V. vulnificus. The strain used in this experiment was isolated from sea water and sea products such as common octopus (Octopus variabilis), ark shell (Anadara broughtonii), blue crab (Ericheir japonica), and sea squirt (Synthia roretzi) collected in Pusan area from July to October in 1985. V. vulnificus was frequently isolated in August when temperature of sea water was around $26^{\circ}C$ and rarely isolated in October when temperature of sea water was around $18.5^{\circ}C$. The distinctive biochemical characteristics of V. vulnificus were ONPG hydrolysis positive and fermented lactose and not grown in peptone water contained $8\%$ NaCl. The optical density at 660 nm of the growth of V. vulnificus was reached maximum level after 8 hours of culture at $35^{\circ}C$ in brain heart infusion broth but that of V. vulnificus was little increased at $15^{\circ}C$ for 14 hours. Optimum temperature and pH for the growth of V. vulnificus were around $35^{\circ}C$ and 8.0. The specific growth rate and the generation time of V. vulnificus isolated from the samples were $1.21\;hr^{-1}$, 34 min at $35^{\circ}C$ and $0.61\;hr^{-1}$, 69 min at $25^{\circ}C$, respectively. V. vulnificus did not grow on eosin-methylene-blue agar, salmonella-shigella agar, deoxycholate agar but grew well on Endo agar, xylose-lysine-deoxycholate agar and hektoen enteric agar. On Endo agar, the colonies of V. vulnificus were red and achieved a diameter of 2 to 4 mm as a feature enabling differentiation of V. vulnificus from other Vibrio spp. V. vulnificus grow well on TCBS agar forming green colonies. V. vulnificus refrigerated at $4^{\circ}C$ exhibited a linear decline of its viablity as 1 log cycle in every 16 hours storage, while V. vulnificus freezed at $-18^{\circ}C$ almost became extinct.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.231-238
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• 2009

The present study was conducted to investigate the antimicrobial activities of extracts from approximately 40 different traditional Korean medicinal herbs against S. gallinarum and S. epidermidis. The extracts from Schizandra chinensis Baill., Melia azedarach Linn$\acute{e}$, Caesalpinia sappan Linn$\acute{e}$. and Rhus javanica Linn$\acute{e}$. exhibited high antimicrobial activities against S. gallinarum, whereas the extracts from Melia azedarach Linn$\acute{e}$ and Rhus javanica Linn$\acute{e}$. exhibited high antimicrobial growth for S. epidermidis. Minimum inhibitory concentrations (MIC) of Melia azedarach Linn$\acute{e}$, Caesalpinia sappan Linn$\acute{e}$. and Rhus javanica Linn$\acute{e}$. for S. gallinarum were 1.2 mg/mL, whereas MIC of exracts from Rhus javanica Linn$\acute{e}$. extract for S. epidermidis were 0.6 mg/mL. Heat treatment of the extracts from Schizandra chinensis Baill. and Rhus javanica Linn$\acute{e}$. caused a significant reduction in antimicrobial activities against S. gallinarum. but didn't affect antimicrobial activities against S. edidermidis. Alkaline treatment of the extracts from Schizandra chinensis Baill. caused a significant reduction in antimicrobial activities against S. gallinarum, while similar treatment of the extracts from Rhus javanica Linn$\acute{e}$. caused a significant increase in antimicrobial activities against S. edidermidis. Since extracts from Rhus javanica Linn$\acute{e}$. and Caesalpinia sappan Linn$\acute{e}$. exhibited the highest antimicrobial activities, these extracts at the concentrations of 100, 300 or 500 ppm were added and then bacterial growth-inhibiting activities for S. gallinarum and S. epidermidis by these two extracts were further examined. Optical density at 620 nm ($OD_{620}$) after 24 hours incubation in the absence of Rhus javanica Linn$\acute{e}$. extract ranged from 0.30 to 0.45 compared with $OD_{620}$ value ranging from 0.06 to 0.18 in the presence of 100, 300 or 500 ppm of the extract, indicating that growth of all bacteria was significantly inhibited within 24 hours by the addition of at least 100 ppm of Rhus javanica Linn$\acute{e}$ extract. Value of $OD_{620}$ after 24 hours incubation in the absence of Caesalpinia sappan Linn$\acute{e}$. extract ranged from 0.30 to 0.55 compared with $OD_{620}$ value ranging from 0.05 to 0.15 in the presence of 300 or 500 ppm of the extract, indicating that growth of all bacteria was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Caesalpinia sappan Linn$\acute{e}$. extract. In conclusion, these findings suggest that extracts from Rhus javanica Linn$\acute{e}$. and Caesalpinia sappan Linn$\acute{e}$. may play important roles in antimicrobial activities against S. gallinarum and S. epidermidis.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.237-248
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• 2018

The vertical distribution of hydrometeor before precipitation near the cloud base has been analyzed using a scanning lidar, rawinsonde data, and Cloud-Resolving Storm Simulator (CReSS). This study mostly focuses on 13 Desember 2016 only. The typical synoptic pattern of lake-effect snowstorm induced easterly in the Yeongdong region. Clouds generated due to high temperature difference between 850 hPa and sea surface (SST) penentrated in the Yeongdong region along with northerly and northeasterly, which eventually resulted precipitation. The cloud base height before the precipitation changed from 750 m to 1,280 m, which was in agreement with that from ceilometer at Sokcho. However, ceilometer tended to detect the cloud base 50 m ~ 100 m below strong signal of lidar backscattering coefficient. As a result, the depolarization ratio increased vertically while the backscattering coefficient decreased about 1,010 m~1,200 m above the ground. Lidar signal might be interpreted to be attenuated with the penetration depth of the cloud layer with of nonspherical hydrometeor (snow, ice cloud). An increase in backscattering signal and a decrease in depolarization ratio occured in the layer of 800 to 1,010 m, probably being associated with an increase in non-spherical particles. There seemed to be a shallow liquid layer with a low depolarization ratio (<0.1) in the layer of 850~900 m. As the altitude increases in the 680 m~850 m, the backscattering coefficient and depolarization ratio increase at the same time. In this range of height, the maximum value (0.6) is displayed. Such a result can be inferred that the nonspherical hydrometeor are distributed by a low density. At this time, the depolarization ratio and the backscattering coefficient did not increase under observed melting layer of 680 m. The lidar has a disadvantage that it is difficult for its beam to penetrate deep into clouds due to attenuation problem. However it is promising to distinguish hydrometeor morphology by utilizing the depolarization ratio and the backscattering coefficient, since its vertical high resolution (2.5 m) enable us to analyze detailed cloud microphysics. It would contribute to understanding cloud microphysics of cold clouds and snowfall when remote sensings including lidar, radar, and in-situ measurements could be timely utilized altogether.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.8
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• pp.441-449
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• 2015

Studies on the flocculation of algae using various metal ions were carried out by measurements of optical density(OD) and zeta potential. Cyanobacteria were used as algaes. Flocculation efficiencies of cyanobacteria by an addition of metal ions were determined from OD values, and the effect of metal ions was greater in the order of $Al^{3+}$>$La^{3+}$>$Ho^{3+}$>$Fe^{2+}$>$Ca^{2+}$. Especially for trivalent metal ions, percentages of metal removed from cyanobacteria solutions on flocculation were measured, showing the same order as in flocculation efficiencies. Zeta potentials of cyanobacteria alone were measured with increasing the concentration, found to be all negative voltages, and were increased with increasing the concentration. The effect of pH on zeta potential of cyanobacteria solution was investigated. Below pH 5.5, the zeta potentials were steeply decreased with increasing pH, whereas in the range of $5.5{\leq}pH{\leq}10$ they were almost constant ($-46{\pm}1mV$) even with increasing pH. At a constant concentration of cyanobacteria ($A_{730}=0.25$), an increase in concentration of metal ions caused an increase in zeta potential of cyanobacteria solution, showing that the effect was greater in the order of $Al^{3+}$>$Ho^{3+}$>$La^{3+}{\gg}Mg^{2+}{\geq}Ca^{2+}{\gg}K^+$. At a constant metal concentration, zeta potentials were measured with increasing cyanobacteria concentration, showing that zeta potentials for $K^+$, $Mg^{2+}$ and $Ca^{2+}$ ions were negligibly changed, whereas those of $Ho^{3+}$ and $La^{3+}$ ions were decreased. Moreover, the effect of $Ho^{3+}$ ion on decreasing zeta potential was smaller than that of $La^{3+}$ ion. $Al^{3+}$ ions showed quite a different behavior that with increasing cyanobacteria concentration the zeta potentials increased and decreased thereafter. Hydrolysis of $Al^{3+}$ ions caused a difficulty to investigate coagulation or flocculation of cyanobacteria by measurement of zeta potential.

• Radiation Oncology Journal
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• v.26 no.3
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• pp.166-172
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• 2008

Purpose: The measurement of radiosensitivity of individuals is useful in radiation therapy. Unfortunately, the measurement of radiation survival using a clonogenic assay, which is the established standard, can be difficult and time consuming. The aim of this study is to compare radiosensitivity results obtained from the MTT and clonogenic assays, and to evaluate whether the MTT assay can be used on clinical specimens. Materials and Methods: HCT-8, LoVo, CT-26, and WiDr were the colon cancer cell lines used for this study. The clonogenic assay was performed to obtain the cell survival curves and surviving fractions at a dose of 2 Gy ($SF_2$) as the standard technique for radiosensitivity. Also, the MTT assay was performed for each of the cell lines (in vitro). To simulate clinical specimens, the cell lines were inoculated into nude mice, removed when the tumors reached 1 cm in diameter, and chopped. Next, the tumors were subjected to the same process involved with the MTT assay in vitro. The inhibition rates (IR) of 10 Gy or 20 Gy of irradiation for in vitro and ex vivo were calculated based on the optical density of the MTT assay, respectively. Results: According to $SF_2$ and the cell survival curve, the HCT-8 and WiDr cell lines were more resistant to radiation than LoVo and CT-26 (p<0.05). The IR was measured by in vitro. The MTT assay IR was 17.3%, 21%, 30% and 56.5% for the WiDr, HCT-8, LoVo and CT-26 cell lines, respectively. In addition, the IR measured ex vivo by the MTT assay was 23.5%, 26%, 38% and 53% in the HCT-8, WiDr, LoVo and CT-26 tumors, respectively. Conclusion: The radiosensitivity measured by the MTT assay was correlated with the measures obtained from the clonogenic assay. This result highlights the possibility that the MTT assay could be used in clinical specimens for individual radiosensitivity assays.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.281-286
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• 2009

Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.

• Journal of Sensor Science and Technology
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• v.12 no.6
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• pp.273-281
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• 2003

A stoichiometric mixture for $CdIn_2Te_4$ single crystal was prepared from horizontal electric furnace. The $CdIn_2Te_4$ single crystal was grown in the three-stage vertical electric furnace by using Bridgeman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. The (001) growth plane of oriented $CdIn_2Te_4$ single crystal was confirmed from back-reflection Laue patterns. The carrier density and mobility of $CdIn_2Te_4$ single crystal measured with Hall effect by van der Pauw method are $8.61{\times}10^{16}\;cm^{-3}$ and $242\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CdIn_2Te_4$ single crystal obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.4750\;eV-(7.69{\times}10^{-3}\;eV)T^2/(T+2147)$. After the as-grown $CdIn_2Te_4$ single crystal was annealed in Cd-, In-, and Te-atmospheres, the origin of point defects of $CdIn_2Te_4$ single crystal has been investigated by the photoluminescence(PL) at 10 K. The native defects of $V_{Te}$, $Cd_{int}$, and $V_{Cd}$, $Te_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Cd-atmosphere converted $CdIn_2Te_4$ single crystal to an optical n-type. Also, we confirmed that In in $CdIn_2Te_4$ did not form the native defects because In in $CdIn_2Te_4$ single crystal existed in the form of stable bonds.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.347-352
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• 1983

To characterize humus fractions in soil, visible, ultraviolet and infrared absorption spectra of humic acids in alkaline solutions and hymatomelanic acids in ethanol solutions extracted by Stevenson's method from paddy rice soils, peats, and volcanic ash soils were analyzed. The spectra patterns of both fractions in visible and ultraviolet ranges did not have any peak and the absorbance decreased as the wavelength increased. Visible and ultraviolet spectra of the solutions from all the peats, volcanic ash soils and paddy rice soil were very similar each other but absorbances were slowly declined in the order of volcanic ash soils, peats and mineral paddy soils. The infrared spectra of the two solutions appeared in a typical pattern, showing a few broad peaks. The main absorption bands were in the regions of $3400cm^{-1}$ (hydrogen bonded OH), near $2900cm^{-1}$ (aliphatic CH), $1720cm^{-1}$ (C=O of COOH, C=O of carbonyl), $1625cm^{-1}$ (aromatic C-C conjugated with C=O and/or COO-), $1400-1450cm^{-1}$ (CH stretch), $1200-1250cm^{-1}$ (CaO stretch of phenolic OH or OH-deformation of COOH) and $1050cm^{-1}$. The hymatomelanic acid fractions, however, had spectra that were characterized especially by very distinct absorption at $2900cm^{-1}$ and $1720cm^{-1}$, for aliphatic CH and carbonyl stretching vibration respectively in addition to the weaker bands for COO- or aromatic CH vibration at $1625cm^{-1}$, as compared to humic acid. No differences were noted in the general patterns of the spectograms of both fractions extracted. Analyses of the functional groups revealed little differences between peats and paddy soils, although total acidity and the content of carboxyl groups were decreased in the order of volcanic ash soils, peats and mineral paddy soils.