• BMB Reports
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• v.32 no.5
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• pp.474-479
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• 1999

Using a hybridoma technique, spleen cells of Balb/c mice immunized with human chorionic gonadotropin (hCG) were fused with NS-1 mouse myeloma cells. Two hybrid cell lines, clones KS-8 and KS-19, secreting monoclonal antibodies to hCG, were isolated. KS-8 and KS-19 belong to the immunoglobulin $G_1$ subclass. With the aid of a double-antibody radioimmunoassay, it was established that the KS-8 monoclonal antibody recognizes an immunodeterminant of the $\beta$-subunit of hCG, whereas the KS-19 monoclonal antibody recognizes an epitope present on the $\alpha$-subunit of hCG. The KS-8 monoclonal antibody specifically reacts with human chorionic gonadotropin and shows cross-reactivity of less than 0.3% to other related human glycoprotein hormones. On the other hand, using a hemagglutination test based on antibody-induced agglutination of sheep red blood cells coated with hCG, It was shown that only the KS-19 monoclonal antibody was capable of inducing a positive reaction, although both monoclonal antibodies had similar binding capacity to the coated cells. The results from the dual screening procedures demonstrate that KS-8 and KS-19 monoclonal antibodies show high sensitivity in two different assays, and are hence useful for the qualitative and quantitative determination of hCG by both radioimmunoassay and hemagglutination inhibition tests.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.129-129
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• 2013

Nanometal alloy catalysts have been found to significantly increase catalytic efficiency, compared to the monometallic counterparts. This enhancement can be attributed to various alloying effects: i) the existence of uniquemixed-metal surface sites [the so called ensemble (geometric) effect]; ii) electronic state changes due to metal-metal interactions [the so called ligand (electronic) effect]; and iii) strain caused by lattice mismatch between the alloy components [the socalled strain effect]. In addition, the presence of low-coordination surface atoms and preferential exposure of specific facets [(111), (100), (110)] in association with the size and shape of nanoparticle catalysts [the so called shape-size-facet effect] can be another important factor for modifying the catalytic activity. However, mechanisms underlying the alloying effect still remain unclear owing to the difficulty of direct characterization. Computational approaches, particularly the prediction using first-principles density functional theory (DFT), can be a powerful and flexible alternative for unraveling the role of alloying effects in catalysis since those can give us quantitative insights into the catalytic systems. In this talk, I will present the underlying principles (such as atomic arrangement, facet, local strain, ligand interaction, and effective atomic coordination number at the surface) that govern catalytic reactions occurring on Pd-based alloys using the first-principles calculations. This work highlights the importance of knowing how to properly tailor the surface reactivity of alloy catalysts for achieving high catalytic performance.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.95-98
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• 2000

An immunochemical method has been develooped as the most sensitive tool for studying the expression of quinoproteins containing pyrroloquinoline qinone(PQQ) in E. coli. The PQQ was conjugated to bovine serum albumin (BSA), and the conjugant was purified by using a $KwikSep^{TM}$ dextran desalting column chromatography. The PQQ-BSA conjugant was immunized to rabbits, and the IgG fractions of the antisera were purified. The most sensitive antibody against PQQ-BSA conjugant recognized some nanogram quantity of the antigen on the blot, but had little cross reactivity with BSA. Using this batch of the antibody, all the immunochemical assays of quinoproteins in E. coli were preformed. Some six different PQQ-specfic spots were detected by Western blot analysis of the soluble proteins in E. coli were performed. Some six different PQQ-specific spots were detected by Western blot analysis of the soluble proteins in E. coli after two-dimensional gel electrophoresis. Their molecular weights on the blot were estimated to be about 100-, 90-, 72-, 58-, 52-, and 50kDa. Their pI values fell in the range from 4.8 to 5.5. These results stronly suggest that quinoproteins are present in E. coli, and that the protein moieties were covalently bound to PQQ.

• Journal of the Korean Applied Science and Technology
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• v.15 no.4
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• pp.45-56
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• 1998

Methyl fructoside oleic acid polyester(MFPE), fructose-based sugar polyester, was synthesized by solvent-free, soap-free transesterification of methyl oleate with methyl fructoside(MF) as a sugar starting material in the presence of conventional potassium carbonate basic catalyst. Methyl fructoside was found to be an effective sugar starting material, because of its low softning point, high heat stability, high miscibility, and high reactivity than other sugars. Yield 98% of purified MFPE based on initial weight of MF was obtained at 1:5 of the molar ratio of methyl fructoside to methyl oleate, 2%(w/w) of potassium carbonate catalyst content, 20${\sim}$200mmHg of reduced pressure and $180^{\circ}C$ of reaction temperature. MFPE structure was confirmed by infrared and proton nuclear magnetic resonance spectroscopy. Physical properties of methyl of fructoside oleic acid polyester such as viscosity, HLB, solubility, color, refractive index, specific gravity, and density were similar to physical properties of sucrose polyesters(SPE) and vegetable oils. Then, it was elucidated that MFPE was sufficient to replace the SPE and conventional oils.

• Journal of the Korean Chemical Society
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• v.11 no.2
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• pp.51-55
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• 1967

A procedure, which is effective enough to label various compounds at low temperature by radioactive iodine, was investigated. The chloramine-T procedure was mostly effective for labelling various protein, amino acids, hormones, and organic compounds by iodine, and the procedure was able to afford both high specific activity and high radiochemical yield. However, the procedure was ineffective for labelling unsaturated compounds or other organic compounds which has not active aromatic nucleus of reactive character. The radiochemical yield of the procedure was generally averaged from 100% to 60%. The reactivity of the aromatic part of the organic compound towards this reagent was correspond to that of an electrophillic reagent. The procedures were described and the reaction path was considered.

• Corrosion Science and Technology
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• v.14 no.6
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• pp.288-295
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• 2015

The present work addresses crevice and galvanic corrosion processes occurring at the cylinder head gasket/cylinder head interface and cylinder head gasket/cylinder liner interface of four-stroke medium-speed diesel engines for marine applications. The contact between these systems and the marine environment can promote formation of demanding corrosion conditions, therefore influencing the lifetime of the engine components. The electrochemical behavior of various metals and alloys used as head gasket materials (both ferrous alloys and copper alloys) was investigated. The efficacy of corrosion inhibitors was determined by comparing electrochemical behavior with and without inhibitors. In particular, crevice corrosion has been investigated by electrochemical tests using an experimental set-up developed starting from the requirements of the ASTM G-192-08, with adaptation of the test to the conditions peculiar to this application. In addition to the crevice corrosion resistance, the possible problems of galvanic coupling, as well as corrosive reactivity, were evaluated using electrochemical tests, such as potentiodynamic measurements. It was possible to quantify, in several cases, the corrosion resistance of the various coupled materials, and in particular the resistance to crevice corrosion, providing a basis for the selection of materials for this specific application.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.63-68
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• 1998

The fluidity of high flowing concrete can be affected by numerous parameters which characterize either the cement of the admixture. The reactivity of a cement as determined by its chemical composition(especially its $C_3$A content), its fineness and its content in sulfates and alkalies obviously plays a key role in rheology of high flowing concrete in fresh state. Specific properties of high range water reducing AE agent used to enhance the workability of high flowing concrete also exert important influence. The purpose of this experimental study is to investigate and analyze the effect of cement and high range water reducing AE agent in fluidity, setting, compressive strength of high flowing concrete. As a result, we found that fluidity of high flowing concrete is affected greatly by kind of cement and high range water reducing AE agent, also, there is harmonic character between high belite cement and polycarbonic acid high range water reducing AE agent.

• Korean Journal of Adult Nursing
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• v.28 no.4
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• pp.388-398
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• 2016

Purpose: The purposes of this study were to identify nurses' empathy, attitude and pain management for patients with dementia and the factors associated with their performance of pain management. Methods: The study design was a cross-sectional survey. The participants in the study were 114 nurses working at 12 geriatric hospitals. This study utilized the Interpersonal Reactivity Index (IRI), which measures four empathy factors. Nurses' attitudes toward pain and performance of pain management, and general and pain related characteristics were measured by self-administered questionnaires. Results: Barriers to pain management for patients with dementia were absence of guidelines, prejudice of pain in dementia, and lack of time and knowledge deficit. There was a significant positive correlation between empathic concern and attitudes, perspective-taking of empathy and pain management. There was also a correlation between empathy and pain management. Stepwise linear regression analysis indicated that the significant factors affecting the performance of pain management included perspective-taking of empathy, use of pain management in dementia guideline and attitudes toward pain. These factors explained 24.0% of variance. Conclusion: The findings from this study suggest that empathy and positive attitude are the important provider attributes which needs to be enhanced by educational programs. It is also necessary to develop and disseminate guidelines for a dementia specific pain management.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.313-317
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• 2013

According to increase of travel, the cases of imported echinococcosis have been increasing in Korea. The present study was undertaken to develop a serodiagnostic system for echinococcosis in Korea. For diagnosis of echinococcosis, the fluid of Echinococcus granulosus hydatid cysts was collected from naturally infected sheep in Uzbekistan. Also serum samples of infected patients who were surgically confirmed were collected in a hospital in Tashkent, Uzbekistan. According to the absorbance of 59 echinococcosis positive and 39 negative control serum samples, the cut-off value was determined as 0.27. The sensitivity and specificity of ELISA with hydatid fluid antigen were 91.5% and 96%, respectively. The antigen cross-reacted with the serum of some cysticercosis or clonorchiasis patients. However, immunoblot analysis on the cystic fluid recognized antigenic proteins of 7-, 16-, and 24-kDa bands in their dominant protein quantity and strong blotting reactivity. In conclusion, the present ELISA system using hydatid cyst fluid antigen from Uzbekistan sheep is sensitive and specific for diagnosis of echinococcosis cases.

• Membrane Journal
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• v.23 no.2
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• pp.101-111
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• 2013

Nano materials having large surface area, uniform dimensions or pores can be utilized in various membrane applications. Recently, many studies have been focused on the application of nano materials and nano technologies in membrane applications by the help of the discovery and development of nano technologies. in terms of mass transport channels or functional modification. However, there have been several technological limitations for commercialization. Nano materials and nano technologies can improve 1) permeability, selectivity, 2) mechanical, chemical, thermal stability or fouling tolerance of conventional membranes and even 3) introduce new functionalities such as specific affinity and reactivity.