• The Journal of the Korean Society for Microbiology
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• v.35 no.3
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• pp.239-250
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• 2000

Sixty-eight clinical isolates of Stenotrophomonas maltophilia from inpatients of 2 university hospitals in Taegu were epidemiologically analyzed by using the minimum inhibitory concentrations of 25 antimicrobial drugs, biochemical reaction, pulsed-field gel elctropgoresis (PFGE), and PCR with enterobacterial repetitive intergenic consensus sequences as primer (ERIC-PCR). 1. All the strains were susceptible to minocycline. More than 57% were susceptible to sulfisomidine (Su), ciprofloxacin (Ci), Ofloploxacin (Of), nalidixic acid (Na), and chloramphenicol (Cm), and $19{\sim}35%$ to ceftazidime (Cd), trimethoprim (Tp), Ticacillin-clavulanic acid, and cefoperazone-sulbactam. Most isolates were resistant to ${\beta}$-lactam antibiotics such as ampicillin (Ap), carbenicillin (Cb), cefotaxim (Ct), cefoxitin (Cx), and aminoglycosides including gentamicin (Gm), tobramycin (Tb), amikacin (Ak). 2. All the isolates were multiply resistant of 5 to 17 drugs and showed 40 different resistance pattern types. 3. All the strains showed very similar biochemical reactions except ${\beta}$-galactosidase and nitrate reduction test. Fourteen strains selected randomly were classified 10 different pattern type by PFGE and ERIC-PCR. These two methods showed identical result. Four strains isolated from wound in 1994 showed similar MIC pattern and identical API 20NE profile, PFGE, and ERIC-PCR pattern indicating episodes of cross-infection among patients. These results indicate that PFGE or ERIC-PCR profile has comparable discriminatory power for epidemiological typing of S. maltophilia.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.1-10
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• 1996

Xanthomonas campestris pv. vesicatoria의 감염으로 토마토 잎조직에 $\beta$-1, 3-Glucanases와 chitinases가 합성, 축적되었다. 그러나 접종되지 않은 건전한 잎에서는 위의 두 가지 가수분해 효소는 매우 낮은 수준으로 유지되었고, 이 두 가지 효소는 친화적 상호작용에서보다는 불친화적 상호작용에서 더욱 높은 수준으로 존재하였다. 이것은 $\beta$-1, 3-glucanases와 chitinases가 X. c. pv. vesicatoria의 생육에 대한 방어기작으로서 중요한 역할을 한다는 것을 시사해 주고 있다. Native PAGE 젤 상에서 $\beta$-1, 3-glucanases를 분리한 결과, 병징 발현이나 저항성 발현에 중요한 역할을 하는 것으로 생각되는 산성 isoform Ga 1과 염기성 isoform Gb 1의 isoform bands만 확인되었다. Isoelectric focusing을 이용하였을 때, 적어도 pI 6.4와 pI 8.6을 지닌 두 개의 $\beta$-1, 3-glucanases의 isoform을 확인할 수 있었고, 특히 불친화적 상호작용에서 더욱 뚜렷하게 유도되었다. 이것은 병 진전과정에서 X. c. pv. vesicatoria에 대해 저항성 발현에 관여한다는 것을 나타내고 있다. 산성 chitinase isoform인 Ca 1의 활성은 병원균의 감염이 진전되는 동안 감소하였다. 또한 다섯 개의 염기성 chitinase isoform이 감염된 토마토 잎 조직에서 발견되었는데, 특히 토마토의 방어기작에 관여하여 병원화적 균주 Bv5-4a에 감염된 잎에서만 유도, 축적되었다. Isoelectric focusing(IEF)을 이용한 후 적어도 2개의 산성과 4개의 염기성 chitinase isoform이 감염된 토마토 잎 추출액에서 확인되었다. Native PAGE 젤에서 isoform Cb 1에 해당되는 pI 9.5를 지닌 chitinase isoform은 오직 불친화적 상호작용에서만 확인되었다. 이온이 제거된 Triton X-100을 처리하여 renaturation 시킨 후에 SDS-PAGE 젤 상태에서 23 kDa과 26 kDa을 지닌 2개의 chitinase isoform을 확인하였다.

• Imaging Science in Dentistry
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• v.38 no.1
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• pp.23-27
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• 2008

Purpose: The aim of this study was to evaluate the change in the position of the mandibular condyle within articular fossa by a CBCT after wearing complete denture (CD). Materials and Methods: CBCT of 34 temporomandibular joints were taken from 9 male and 8 female patients with CB $Mercuray^{TM}$ (Hitachi, Japan) before and after wearing a CD for rehabilitation. Position of mandibular condyle within articular fossa at centric occlusion was evaluated with $Vimplant2.0^{TM}$ (CyberMed, Korea) on the central parasagittal view and curved panoramic coronal view of the condylar head. A statistical evaluation was done with SPSS. Results: The range of anteroposterior positional rate (AP) of condylar head within articular fossa was -16-5 and -10-12 respectively on the right and left sides. Before wearing CD, the AP rate showed discrepancy between right and left sides (p<0.05). After wearing CD, both condyles showed a tendency to decrease in posterior condylar position (right side; p<0.05). The average discrepancy between right and left side in mediolateral positional rate (MD) was 15.5 and 4.5 respectively before and after wearing CD. The improvement was observed in mediolateral relationship of both condylar heads after wearing CD (p< 0.01). Before wearing CD, the average horizontal angle of long axis of condylar head was $79.6{\pm}2.7^{\circ}\;and\;80.1{\pm}5.7^{\circ}$ respectively on the right and left sides. After wearing CD, both condyles were rotated in the same direction in average on axial plane. Conclusion: We observed with CBCT the significant clinical evidence in case of positional change of mandibular condyle after wearing complete denture.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.267-273
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• 2011

Methyl violet, used extensively in the commercial textile industry and as a biological stain, is a hazardous recalcitrant. Aspergillus sp. strain CB-TKL-1 isolated from a water sample from Tsumoriri Lake, Karzok, Ladakh, India, was found to completely decolorize methyl violet within 24 h when cultured under aerobic conditions at $25^{\circ}C$. The rate of decolorization was determined by monitoring the decrease in the absorbance maxima of the dye by UV-visible spectroscopy. The decolorization of methyl violet was optimal at pH 5.5 and $30^{\circ}C$ when agitated at 200 rpm. Addition of glucose or arabinose (2%) as a carbon source and sodium nitrate or soyapeptone (0.2%) as a nitrogen source enhanced the decolorization ability of the culture. Furthermore, the culture exhibited a maximum decolorization rate of methyl violet after 24 h when the C:N ratio was 10. Nine N-demethylated decolorized products of methyl violet were identified based on UV-visible spectroscopy, Fourier transform infrared (FTIR), and LC-MS analyses. The decolorization of methyl violet at the end of 24 h generated mono-, di-, tri-, tetra-, penta-, and hexa-N-demethylated intermediates of pararosaniline. The variation of the relative absorption peaks in the decolorized sample indicated a linear decrease of hexa-N-demethylated compounds to non-N-demethylated pararosaniline, indicating a stepwise N-demethylation in the decolorization process.

• Elastomers and Composites
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• v.44 no.3
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• pp.269-273
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• 2009

A study on the life-time expectation of a CR-modified NR rubber composite through the change of thermal degradation characteristics was performed using both isothermal thermogravimetric analysis (TGA) and thermomechanical analysis (TMA). Master curves at reference temperature of $90^{\circ}C$ could be obtained with shift factor $a_T$, which was determined empirically using Time-Temperature Superposition Principle (TTSP). Activation energies could be calculated from the slope of Arrhenius plot of shift factor and showed similar values of $E_{a,TGA}$= 41.2 and $E_{a,TMA}$= 54.5 kJ/mol, respectively. It was considered from the results that chemical degradation resulting weight loss of the sample might be closely related to a physical degradation such as the dimensional change of the sample.

• Journal of the Korean Chemical Society
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• v.28 no.5
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• pp.328-334
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• 1984

A series of phenyl N-benzenesulfonylchloroformimidate derivatives (p-H, p-Cl, p-CH3 & p-OCH3) were prepared and the hydrolysis of these compounds were studied kinetically at various pH by UV spectrophotometry in 1 ; 4 dioxane-water at $25^{\circ}C$. Hammett ${\rho}$ values measured at pH 5.0 (${\rho}$ = -0.45) and pH 10.0 (${\rho}$ = 0.40) indicate that the reaction proceeds via an azocarbonium ion intermediate in the acidic medium, whereas, it involves direct attack by hydroxide ion on the azomethine carbon atom occurs under the basic medium. The formation of stabilized azocarbonium ion species at pH 5.0 is also consistent with the large solvent effect(m = 1.3-1.5 & n = 5.0-5.5). On the basis of these findings, we may concluded that the hydrolysis of phenyl N-benzenesulfonylchloroformimidate derivatives proceeds by $SN_1$ below pH 8.0, however, above pH 10.0, the hydrolysis proceeds through $SN_2$ and in the range of pH 8.0-10.0, these two reactions occur competitively.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.2
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• pp.156-163
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• 2006

CF systems are widely used in recommendation due to the easy implementation and the outstanding performance. They have several problems such as the sparsity problem, the first-rater problem, and recommending explanation. Many studies are suggested to resolve these problems. While the influence of the sparsity problem lessens as the users' data are accumulated, but the first-rater problem is originated from the CF systems and there are a number of researches to overcome the disadvantages of CF systems based on the content-based methods. Also CF systems are black boxes, providing no explanation of working of the recommendation. In this paper we present a content-based prediction system based on the preference words, which exposes the reasoning behind a recommendation. Our system predicts user's rating of a new movie and we suggest a semiotic network-based method to solve the mismatching problem between the items. For experimental comparison, we used EachMovie and IMDb dataset.

• Journal of the Korea Institute of Building Construction
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• v.13 no.4
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• pp.321-332
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• 2013

Costs and expenses are intertwined and incurred throughout an entire construction project, even from the pre-construction phase, and each phase has a different impact on the life cycle cost (LCC). However, the cost breakdown structure (CBS) is different in each phase of a building construction project, which makes it hard to reasonably calculate construction cost. For this reason, the boundary conditions were analyzed in this study based on the life cycle cost break structure (LCCBS). In addition, breakdown factors were analyzed based on the boundary conditions to derive a linkage method. The validity of the linkage method was verified through application to actual construction projects. Through the analysis, it was found that the problem of items being left out was reduced by more than 97.2 percent, and the work was done an average of 6 hours faster compared to the conventional method. It is expected that by applying the new LCC system, LCC will be both reduced and calculated in a more efficient manner.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.155-162
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• 1989

This experiment was conducted to investigate the endosperm characteristics of an opaque rice which was derived from an Indica cultivar Pokhareli Mashino. Grain apperance of opaque rice looked similar to the waxy grain, while the blue-color response to the iodine solution was similar to non-waxy endosperm. The shape of starch granules was alike each other, but their size were different each other with the smallest of the opaque rice. Their cristaline structure of starch granules were A type. The content of total protein and most of the amino-acids of opaque rice was about 1.5 times of other varieties. Alkali digestibility of the opaque rice was very low. Total water uptake and hydration rate of opaque rice was similar to non-waxy variety Tongil. Amylogram characteristics such as viscosity, setback and consistency of opaque rice revealed medium value between. waxy and non-waxy rice.

• Analytical Science and Technology
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• v.17 no.4
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• pp.347-354
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• 2004

We collected crucians (Carassius auratus) and leopard frogs(Rana pipiens) along the Nakdong River and the basin area at five locations from Koomi to Nakdong-estuary. The muscular tissue were separated and a GC-MSD system was used for quantification of PCBs. The 62 PCB congeners which represent total PCB levels were selected as analytes. We determined concentrations of PCBs and studied distribution characteristics by individual congeners and homologs. In the crucian, 24 congeners were detected and total PCB levels ranged from 0.74 to 5.41 ng/g wet weight. In the leopard frog, however, only 2 congeners were detected from Nakdong estuary only. The PCB level was 0.24 ng/g wet weight, around 22 times lower than the crucians. The PCB 153 showed the highest concentrations in the congeners and penta- and hexa-CBs showed the strong predominance which accounted for 78% of the total PCBs.