• Journal of Environmental Science International
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• 제15권12호
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• pp.1093-1101
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• 2006

In the present study we studied the growth, photosynthetic traits and protective mechanisms against oxidative stress in the primary loaves of cucumber (Cucumis sativus L.) seedlings with or without UV-B treatment. Cucumber seedings were irradiated with UV-B for 10 days in environment-controlled growth chambers. The primary leaves irradiated with UV-B showed reduction in leaf length and decreased biomass production. The reduced biomass production seemed to be due to a negative effect of UV-B radiation on the photosynthetic process. Changes in chemical properties of leaf, such as chi a/b ratio affected photosynthesis. UV-B significantly affected chl b content compared with chi a in the light harvesting complex resulting reduced photosynthetic activity Fv/Fm decreased with an UV-B stress, suggesting that the photosynthetic apparatus, and particularly, PS II was damaged under UV-B stress. Malondialdehyde(MDA) concentration which represents the state of membrane lipid peroxidation Increased significantly under UV-B stress confirming an oxidative stress. UV-B exposure with SA solution(0.1-1.0 mM) can partially ameliorated some of the detrimental effects of UV-B stress. Leaf injuries including loss of chlorophyll and decreased ratio of Fv/Fm were reduced with combined application of UV-B and SA. ABA and JA showed similar mode of action in physiological effects on photosynthetic activities though the levels were lower than those from SA treated plants. Chloroplast ultrastructure was also affected by UV-B exposure. The thickness of leaf tissue components decreased and the number of grana and thylakoids was reduced in chloroplast applied UV-B or SA alone. At combined stress granal and stromal thylakoids were less affected. The leaves under combined stress acquired a significant tolerance to oxidative stress. From these results, it can be suggested that SA may have involved a protective role against UV-B induced oxidative damage.

• Journal of the Korean Society of Food Culture
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• 제17권2호
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• pp.165-170
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• 2002

In order to economically utilize dough with B. longum, B. infantis and B. brevis as a bread improver, aerotolerance, ${\alpha}-galactosidase$ activity, organic acids, farinograph and extensograph of dough were investigated. In aerotolerance of Bifidobacterium sp., B. longum was highest among tested starters, followed by B. infantis. The ${\alpha}-galactosidase$ activity was highest in the B. longum among tested starters. In organic acids, the contents of lactic acid and acetic acid were the highest in the among tested starters, followed by B. infantis. In farinograms of dough, water absorption and peak time were highest in the B. brevis among tested dough. Extensogram showed that the area increased remarkably in B. longum and B. infantis at 135min of fermentation. Extensibility and resistance to extension of dough were highest in the B. infantis among the dough, followed B. longum.

• Journal of Environmental Science International
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• 제7권5호
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• pp.633-638
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• 1998

To determine whether the enhanced UV-B causes oxidative stress, and to test the relationship between plant growth response and biochemical defense response to UV-B, two soybean plants, Keunolkong, a highly UV-B susceptible cultivar, and Danyeubkong, a less UV-B susceptible cultivar, were subjected to the enhanced UV-B [daily dose : 0.06 (control) and 11.32 (enhanced UV-B) kJ $m^{-2}$ ; $UV-B_{BE}$] for 3 weeks. Contents of malondialdehyde and total carotenold were increased in Keunolkong compared with Danyeubkong by UV-B. In control plants, ascorbate level of Danyeubkong was 3 times higher than that of Keunolkong. The ratio of dehydroascorbate/ascorbate was highly increased in Keunolkong by UV-B . The activities of antioxidative enzyme such as superoxide dismutase, ascorbate peroxidase, monodehydroascorbate reductase and glutathione reductase were increased in both cultivars by UV-B. This results indicate that enhanced UV-B caused oxidative stress in both two cultivars, especially in Keunolkong. Susceptibility of two soybean cultivars to UV-B is closely related to the levels of antioxidants such as carotenoid and ascorbate.

• Fibers and Polymers
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• 제3권1호
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• pp.8-13
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• 2002

The effect of block sequence on the self-assembly of ABC-type triblock copolymers in the ordered state is investigated using an isothermal-isobaric molecular dynamics simulation. The block sequence has an important effect ,on the ]norphology of ABC triblock copolymers. Different morphologies are observed depending on the block sequence as well as the block composition. The triblock copolymers with the volume fraction of 1 : 1 : 1 ($f_A$=$f_B$=$f_C$= 0.33) show the three phase and four layered lamellar structures irrespective of the block sequence. The $A_{32}$$B_{16}$$C_{32}$triblock copolymer with $f_B$=0.2 shows a morphology In which cylinders of midblock B are formed at the interface between A and C lamellae, whereas the morphology of triblock copolymer $B_{16}$$C_{32}$ $A_{32}$ and $C_{32}$ $A_{32}$ $B_{16}$ show a cylindrical core-shell structure and a lamellar type morphology, respectively. The $A_{20}$$B_{40}$$C_{20}$the triblock copolymer with the block B as a major component shows a tricontinuous structure, whereas both $B_{40}$$C_{20}$$A_{20}$ and $C_{20}$$A_{20}$$B_{40}$ triblock coolymers exhibit the lamellar structures. When the block B has larger volrome fraction with $f_B$=0.75, the matrix is composed of block B, and other two blocks A and C form spherical domains.

• Journal of the korean academy of Pediatric Dentistry
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• 제29권3호
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• pp.376-381
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• 2002

The purpose of this study was to analyse the color of natural deciduous teeth in Korean children and to compare with that of composite resin specimens. The subjects were 148 children (80 boys and 68 girls) with good general condition and normal teeth color, aged between 3 and 6 years. The color of middle third of maxillary central incisor in deciduous teeth was examined with shade guide and then measured by means of the colorimeter CV300 which can be measured by CIELAB system. The data were analyzed statistically by SPSS program. The results were summerized as follows; 1. Over 90% of the color for the deciduous anterior teeth was in A1, A2, B1, B2 and P shade. 2. The means of deciduous teeth color were $L^*=58.72,\;a^*=-1.18,\;b^*=-0.63$ by colorimeter CV300. 3. $L^*,\;a^*\;and\;b^*$ prices for A1, A2, B1, B2, P were $L^*=52.52,\;a^*=-1.90,\;b^*=1.18$ in A1 specimen, $L^*=54.90,\;a^*=-1.87,\;b^*=1.60$ in A2 specimen, $L^*=59.80,\;a^*=-2.70,\;b^*=-0.63$ in B1 specimen, $L^*=56.90,\;a^*=-1.70,\;b^*=1.63$ in B2 specimen, $L^*=52.93,\;a^*=-2.33,\;b^*=1.10$ in P specimen. The means of B1 color specimen were most similar to those of deciduous teeth color. The A1 color values were similar to the P color values. 4. The standard deviation of $L^*,\;a^*$ was small among colors, but that of $b^*$, in the yellowish color, was large.

• Honam Mathematical Journal
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• 제39권3호
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• pp.417-430
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• 2017

In this paper, we investigate the stability of a functional equation $$2f(ax+by)+abf(x-y)+abf(y-x)-{\frac{2af((a+b)x)}{a+b}}-{\frac{bf((a+b)y)}{a+b}}-{\frac{bf(-(a+b)y)}{a+b}}=o$$ by applying the direct method in the sense of Hyers and Ulam.

• Journal of the Korean Crystal Growth and Crystal Technology
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• 제11권1호
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• pp.20-26
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• 2001

Titanium boride ($\textrn{TiB}_{x}$) films were deposited on (100) silicon substrates at the substrate temperature of $500^{\circ}C$ by means of the co-evaporation of titanium and boron evaporants during deposition. The co-evaporation method makes it possible to deposit the non-stoichiometric films with different boron-to-titanium ratio($0{\le}B/Ti \le 2.5$). The resistivity increases linearly as the boron-to-titanium ratio in the as-deposited films is increased. The surface roughness of $\textrn{TiB}_{x}$ films is changed as a function of the boron-to-titanium ratio. The XRD spectrum for pure titanium film shows a highly (002) preferred orientation. For B/Ti=0.59 ratio only a single TiB phase that shows a (111) preferred orientation is observed. However, the $\textrn{TiB}_{x}$ phase with the hexagonal structure of the $AlB_2$(C32) type appears as the boron concentration increase, and only a single $\textrn{TiB}_{x}$ phase is observed for $B/Ti \ge 2.0$ ratio. The $\textrn{TiB}_{x}$/Si samples reveal a tensile stress (3~$20{\times}^9$dyn/$\textrm{cm}^2$) in the overall composition of the films, although the magnitude of the residual stresses is depended on the nominal B/Ti ratio.

• Korean Journal of Mathematics
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• 제26권1호
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• pp.61-74
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• 2018

Let $\mathcal{A}$ and $\mathcal{B}$ be two prime ${\ast}$-algebras. Let ${\Phi}:\mathcal{A}{\rightarrow}\mathcal{B}$ be a bijective and satisfies $${\Phi}(A{\bullet}B{\bullet}A)={\Phi}(A){\bullet}{\Phi}(B){\bullet}{\Phi}(A)$$, for all $A,B{\in}{\mathcal{A}}$ where $A{\bullet}B=A^{\ast}B+BA^{\ast}$. Then, ${\Phi}$ is additive. Moreover, if ${\Phi}(I)$ is idempotent then we show that ${\Phi}$ is ${\mathbb{R}}$-linear ${\ast}$-isomorphism.

• Biomolecules & Therapeutics
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• 제7권1호
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• pp.14-21
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• 1999

The immunogenicity of the recombinant human basic fibroblast growth factor (rh-bFGF) was investigated by tests for active systemic anaphylaxis (ASA), passive cutaneous anaphylaxis (PCA), passive hemagglutination (PHA) and guinea pig maximization test (GPMT) in mice or guinea pigs. Guinea pigs were sensitized with rh-bFGF ($100-1000\;\mu\textrm{g}/kg$) or rh-bFGF-CFA mixture ($1000\;\mu\textrm{g}/kg$). All animals sensitized with rh-bFGF alone or mixture with CFA showed symptoms of anaphylactic shock. IgE antibodies to rh-bFGF were detected in sera obtained from rh-bFGF and rh-bFGF-Alum ($1000\;\mu\textrm{g}/kg$) sensitized mice, indicating that rh-bFGF has immunogenicity eliciting potential. IgG and/or IgM antibodies to rh-bFGF were also detected in all the sera obtained from sensitized mice by PHA. In the GPMT for delayed type skin reaction, no skin reaction was observed in sensitized guinea pigs after intradermal injection and dermal application of 0.01% rh- bFGF. However, these positive reactions were consistent with the results of another rh-bFGF, showing that rh- bFGF is a heterogenous protein to rodents. Considering the fact that rh-bFGF is a genuine human protein of which structure is identical to the endogenous human bFGF, it is thought that rh-bFGF is rarely associated with immunological problems in clinical use.

• Journal of the Korean Home Economics Association
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• 제42권2호
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• pp.117-131
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• 2004

The purpose of this study was to examine the current situation of B2B fashion buying behavior (i.e., buying motives, product characteristics, buying processes), and to analyze the buying performance, buying problems and buying strategies. In depth, face-to-face interviews with structured questionnaire were conducted with three buyers and three vendors related to 18 buying items of C Company. Results of this research were as following:1. Buying motives were mainly reduction of buying costs, improvement of profits, and increased efficiency in buying process for retail buyers, while the selling motive was mainly improvement of market share for suppliers. Suitable items for B2B buying were basic items or bulk items. The B2B buying process included the following steps: selecting auction items, target prices, and suppliers ; setting the product specification and bidding niles; training the suppliers for preparing the auction; proceeding the auction by internet. 2. The perceived B2B benefits for buyers were profit improvement and cost reduction while those for suppliers were time saving and market share improvement. The indicated buying problems were as poor product quality, low product image, and difficulty in partnership. For B2B buying strategies, a quality management system, various auction tactics based on items, and a supplier management system were recommended.