• The Journal of the Korean Society for Microbiology
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• v.21 no.2
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• pp.171-179
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• 1986

The HLA class II region encodes a series of polymorphic glycoproteins that form cell surface heterodimers each consisting of one $\alpha$ and one $\beta$ chain. Thess class II molecules are encoded by genes clustered within three loci. DP, DQ, and DR are functfonally implicated as regulatory signals in intercellular communication during the immune resposes. The phenotypic hallmark of the HLA complex is a high degree of structural and functional polymorphism. Detailed analysis. of such polymorphisms should aid in understanding the molecular basis for associations between HLA and diseases. We have used techniques of restriction enzyme fragment analysis by Southern blotting to investigate polymorphisms associated with DQ $\beta$ class II genes on haplotypes expressing the HLA-DR4 and -DQw3 specificities. The endonucleases Hind III and Bam HI were used to identify a specific DQ $\beta$ genomic polymorphism that precisely corrresponds with the reactivity of a monoclonal antibody A-10-83, previously shown to define a serologic split of DQw3. This study identifies two allelic DQ va. riants. DQw3.1 and DQw3.2. We used these specific genotypic markers to investigate the genomic basis of the association of DR4 with insulin-dependent diabetes mellitus(IDDM) and seropositive juvenile rheumatoid arthritis(JRA). The DR4 positive IDDM demonstrate the predominant expression of DQw3.2 and the very rare expression of DQw3.l. However, in haplotype matched siblings from two IDDM families, all of the DR4 positive siblings display a IDDM-associated DQw3.2 allele. Thus, both affected and healthy individuals can carry the same haplotypes and genomic markers, demonstrating that thess specific allelic variants are genetic elements that indicate a increased risk of IDDM but are not in fact disease specific. We contrasted this result with a similar analysis of patients with another DR4-associated disease, JRA. In contrast to the preponderance of the DQw3.2 allele in IDDM, the JRA patients expressed either the DQw3.1 or the DQw3.2 allele and sometimes both, without apparent association with disease expession. The different genomic markers reported here within HLA-DQ region potentially an analysis of HLA-associated function and disease susceptibility.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.30-36
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• 1994

choChorion(egg-shell) morphology of the F1 hybrid between Bombyx mori and Bombyx mandarina has been observed by scanning electrom microscope and chorion protein was analyzed by electrophoresis. The chorion surface structure of F1 hybrids in the lateral(flat) region was similar to that of maternal line. The F1 hybrids chorion was found to have basically a three layer structure. The middle and inner layer were very much like those of the Bombyx mandarina and Bombyx mori. There were many conic pillar structures in the outer layer of the F1 hybrid, which was similar to Bombyx mandarina. This conic pillar structure had a thin cover layer was more clear in the dorsal and ventral side of the F1 hybrid chorion. The conic pillar structure of Bombyx mandarina was found to be dominant in F1 hybrid chorion irrespective of their maternal line. Major components of chorion protein were analyzed by two-dimensional electrophoresis and found to have isoelectric points in the range of pH 4.0-6.5 and molecular weight 10 to 50 kd. F1 hybrid chorion protein components related directly to those of the maternal line. The conic pillar structure was dominat characteristic and it was present in all F1 hybrid.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.321-326
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• 1994

Korean isolate, porcine epidemic diarrhea virus (KPEDV-9) was adapted through serial passages in vero cell. The viral yield reached up to $10^{5-6}$ $TCID_{50}/ml$ at the passage level of 90th. The cell adapted virus was characterized through genetic and morphological examinations. The RNA extracted from virus infected cell revealed the presence of RNA band with molecular size of >20Kb. The electron microscopic examination on purified virus showed the pleomorphic appearance of enveloped particles with 5-10nm surface projections, which fit with the shape of coronavirus. The etiological survey on swine diarrhea by immunofluorescence test(FA) indicated 17.5% positive rate on the PEDV infection. In addition, the incidence were detected both in piglets within two weeks old as well as fattening pigs. Serological survey by ELISA revealed the overall 45% positive result, thus, indicating the PEDV infection are widespread throughout this country.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.373-380
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• 2013

A severe pink mold rot on matured asian pear (Pyrus serotina Rehder) fruit occurred in the organic farmers' orchard in Jinju, Korea in October, 2012. Decay of pear fruit appeared as a softened water-soaked symptom that was easily punctured by pressure. Later pink mycelium appeared on the surface of pear fruit and produced a mass of powdery pink conidia spores. Optimum temperature for mycelial growth of T. roseum was $25^{\circ}C$. Conidia showed hyaline, smooth, 2-celled, thick-walled with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $10{\sim}22(34){\times}6{\sim}10(12){\mu}m$ in size. Conidiophore was erect, colorless, unbranched type, and 4-5 ${\mu}m$ width. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.59-59
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• 2011

We will report atomically sharp epitaxial growth of $Bi_2Se_3$ three-dimensional topological insulator films on Si(111) substrate with molecular beam epitaxy (MBE). It was achieved by employing two step growth temperatures to prevent any formation of second phase, like as $SiSe_2$ clusters, between $Bi_2Se_3$ and Si substrate at the early stage of growth. The growth rate was determined completely by Bi flux and the Bi:Se flux ratio was kept ~1:15. The second-phase-free atomically sharp interface was verified by RHEED, TEM and XRD. Based on the RHEED analysis, the lattice constant of $Bi_2Se_3$ relaxed to its bulk value during the first quintuple layer implying the absence of strain from the substrate. Single-crystalline XRD peaks of $Bi_2Se_3$ were observed in films as thin as 4 QL. TEM shows full epitaxial structure of $Bi_2Se_3$ film down to the first quintuple layer without any second phases. This growth method was used to grow high quality epitaxial $Bi_2Se_3$ films from 3 QL to 3600 QL. The magneto-transport properties of these thin films show a robust 2D surface state which is thickness independent.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.68-69
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• 2011

The process of charge transfer at the interface between two semiconductors or between a metal and a semiconductor plays an important role in many areas of technology. The optimization of such devices requires a good theoretical description of the interfaces involved. This, in turn, has motivated detailed mechanistic studies of interfacial charge-transfer reactions at metal/organic, organic/organic, and organic/inorganic semiconductor heterojunctions. Charge recombination of photo-induced electron with redox species such as oxidized dyes or triiodide or cationic HTM (hole transporting materials) at the heterogeneous interface of $TiO_2$ is one of main loss factors in liquid junction DSSCs or solid-state DSSCs, respectively. Among the attempts to prevent recombination reactions such as insulating thin layer and lithium ions-doped hole transport materials and introduction of co-adsorbents, although co-adsorbents retard the recombination reactions as hydrophobic energy barriers, little attention has been focused on the anchoring processes. Molecular engineering of heterogeneous interfaces by employing several co-adsorbents with different properties altered the surface properties of $TiO_2$ electrodes, resulting to the improved power conversion efficiency and long-term stability of the DSSCs. In this talk, advantages of the coadsorbent-assisted sensitization of N719 in preparation of DSSCs will be discussed.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.335-344
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• 1992

This study was conducted to investigate the influence of addition of cetyl trimethyl ammo­nium bromide (CTAB), and amine [ethylamine (EA) or ethylene diamine (EDA)] to aqueous sodium hydroxide (NaOH) solution on polyester alkaline hydrolysis, The experimental vari­ables such as CTAB concentration, EA or EDA concentration, NaOH concentration, tempera­ture and time were compared, and the changes in physical and chemical properties of alkaline­hydrolyzed PET fabrics depending on their treated conditions were measured, The results are as follows: 1. By adding CTAB and amine in aqueous NaOH solution, increasing effect on weight loss of PET fabrics was obtained in simultaneous addition of CTAB and EDA, but not in CTAB and EA. 2. By adding CTAB & EDA simultaneously, increasing effect on weight loss was obtained regardless of EDA concentration, time and temperature, and it was more effective at lower NaOH concentration. :l. The increase of void space (or irregularly grooved surface), of softness, of wickability, of dyeability on PET fabric, and the decrease of tensile strength, of molecular weight were observed according to the weight loss on the PET fabrics. These changes were equal to all alkaline-hydrolyzed PET fabrics regardless of addition of CTAB and amine. l. There was little changes on crystallinity, thermal behavior when PET fiber was treated with ,aqueous NaOH solution with CTAB and EDA. These results supported that increasing effect on weight loss take place without inducing of fine structural change of PET fibers.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.268-274
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• 1999

The chitosan solution was prepared by dissolving chitosan into 2 wt % aqueous acetic acid solution and then chitosan beads were made by sol-gel method. The average molecular weight and the degree of deacetylation of the chitosan used here were determined to be $8.2{\times}10^5$ and 85%, respectively. chitosan beads were highly porous which was confirmed by SEM photography and BET. Adsorption equilibrium of $Cu^{2+}$ on porous chitosan beads could be represented by Sips equation. The diffusion of cupric ions in the chitosan beads could be explained by pore and surface diffusion mechanisms. Adsorption dynamics of $Cu^{2+}$ in fixed-bed could be simulated by linear driving force approximation (LDFA). It was proven that porous chitosan beads manufactured in this work are good adsorbents for the removal of $Cu^{2+}$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.1-5
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• 2002

A fusion protein, consisting of a human epidermal growth factor (hEGF) as the recognition domain and human angiogenin as the toxin domain, can be used as a targeted therapeutic against breast cancer cells among others. The fusion protein was expressed as inclusion body in recombinant E. coli, and when the conventional, solution-phase refolding process was used the refolding yield was very low due to severe aggregation. It was probably because of the opposite electric charge at a neutral pH resulting from the vastly different pI values of each domain. The solid-phase refolding process that exploited the ionic interactions between ionic exchanger surface and the fusion protein was tried, but the adsorption yield was also very low, below $ 30\%$, regardless of the resins and pH conditions used. Therefore, to provide a higher ionic affinity toward the solid matrix, six lysine residues were tagged to the N-terminus of the hEGF domain. When heparin-Sepharose was used as the matrix, the adsorption capacity increased 2.5-3 times to about $88\%$. Besides the intrinsic affinity of angiogenin to heparin, the poly-lysine tag provided additional ionic affinity. And the subsequent refolding yield increased nearly 13-fold, from ca. $4.8\%$ in the conventional refolding of the untagged fusion protein to $63.6\%$. The process was highly reproducible. The refolded protein in the column eluate retained RNase bioactivity of angiogenin.

• Journal of Electrochemical Science and Technology
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• v.8 no.2
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• pp.133-145
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• 2017

Palm oil production is among the highest worldwide, and it has been mainly used in the food industry and other commodities. Currently, a lot of palm oil production has been destined for the synthesis of biodiesel; however, its use in applications other than the food industry has been questioned. Thereby for a sustainable development, in this paper the use of palm oil of low quality for corrosion inhibitors synthesis is proposed. The performance of the synthesized inhibitors was evaluated by using electrochemical techniques such as open circuit potential measurements, linear polarization resistance and electrochemical impedance spectroscopy. The results indicate that the fatty amides from palm oil are excellent corrosion inhibitors with protection efficiencies greater than 98%. Fatty amides molecules act as cathodic inhibitors decreasing the anodic dissolution of iron. When fatty amides are added, a rapid decrease in the corrosion rate occurs due to the rapid formation of a molecular film onto carbon steel surface. During the adsorption process of the inhibitor a self-organization of the hydrocarbon chains takes place forming a tightly packed hydrophobic film. These results demonstrate that the use of palm oil for the production of green inhibitors promises to be an excellent alternative for a sustainable use of the palm oil production.