• Polymer(Korea)
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• v.33 no.5
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• pp.441-445
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• 2009

In order to develop an intelligent delivery system for cosmetic active agents (e.g., arbutin, ascorbic acid, and adenosine), pH-responsive P(MAA-co-PEGMA) hydrogel particles having an average size of approx. $2{\mu}m$ and spherical shape were synthesized via dispersion photopolymerization. There was a drastic change in the swelling ratio of P (MAA-co-PEGMA) hydro gels at a pH 5, which is the $pK_a$ of the hydrogel. To determine the factors that have an effect on the loading of cosmetic active agents into the hydrogel, the loading efficiency of the active agents was investigated at various MAA and EG compositions of the hydrogel and the loading pH conditions. When the MAA contents in the hydrogel decreased, the loading efficiency of the active agents increased. In loading experiments with different pH conditions, the active agents showed higher loading efficiency into the hydrogel at the pH where the hydrogel was at the swollen state than at the pH where the electrostatic repulsion was minimized.

• Corrosion Science and Technology
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• v.7 no.1
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• pp.40-44
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• 2008

Passive metal forms an interfacial diffuse layer on the surface of passive film by its reaction with $H^+$ or $OH^-$ ions in solution depending on solution pH. There is a critical pH, called pH point of iso-selectivity ($pH_{pis}$) at which the nature of the diffuse layer is changed from the anion-permeable at pH<$pH_{pis}$ to the cation-permeable at pH>$pH_{pis}$. The $pH_{pis}$ for a passivated Fe was determined by examining the effects of pH on the thickness of passive film and on the dissolution reaction occurring on the passive film under a gavanostatic reduction in borate-phosphate buffer solutions at various pH of 7~11. The steady-state thickness of passive film formed on Fe showed the maximum at pH 8.5~9, and further the nature of film dissolution reaction was changed from a reaction producing $Fe^{3+}$ ion at $pH\leq8.5$ to that producing $FeO_2{^-}$ at $pH\geq9$, suggesting that the $pH_{pis}$ of Fe is about pH 8.5~9. In addition, the passive film formed at pH 8.5~9, $pH_{pis}$, was found to be the most protective with the lowest defect density as confirmed by the Mott-Schottky analysis. Pitting potential was decreased with increasing $Cl^-$ concentration at $pH\leq8.5$ due probably to the formation of anion permeable diffuse layer, but it was almost constant at $pH\geq9$ irrespective of $Cl^-$ concentration due primarily to the formation of cation permeable diffuse layer on the film, confirming again that $pH_{pis}$ of Fe is 8.5~9.

• Molecules and Cells
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• v.21 no.2
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• pp.251-260
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• 2006

During mitosis, genomic integrity is maintained by the proper coordination of anaphase entry and mitotic exit via mitotic checkpoints. In budding yeast, mitotic exit is controlled by a regulatory cascade called the mitotic exit network (MEN). The MEN is regulated by a small GTPase, Tem1p, which in turn is controlled by a two-component GAP, Bfa1p-Bub2p. Recent results suggested that phosphorylation of Bfa1p by the polorelated kinase Cdc5p is also required for triggering mitotic exit, since it decreases the GAP activity of Bfa1p-Bub2p. However, the dispensability of GEF Lte1p for mitotic exit has raised questions about regulation of the MEN by the GTPase activity of Tem1p. We isolated a Bfa1p mutant, $Bfa1p^{E438K}$, whose overexpression only partially induced anaphase arrest. The molecular and biochemical functions of $Bfa1p^{E438K}$ are similar to those of wild type Bfa1p, except for decreased GAP activity. Interestingly, in $BFA1^{E438K}$ cells, the MEN could be regulated with nearly wild type kinetics at physiological temperature, as well as in response to various checkpoint-activating signals, but the cells were more sensitive to spindle damage than wild type. These results suggest that the GAP activity of Bfa1p-Bub2p is responsible for the mitotic arrest caused by spindle damage and Bfa1p overproduction. In addition, the viability of cdc5-2 ${\Delta}bfa1 $ cells was not reduced by $BFA1^{E438K}$, suggesting that Cdc5p also regulates Bfa1p to activate mitotic exit by other mechanism(s), besides phosphorylation.

• Korean Journal of Community Nutrition
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• v.8 no.1
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• pp.102-111
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• 2003

The purpose of this study was to investigate the relationship among serum leptin, nutritional status, and the obesity indices of 55 obese children in Daegu and Kyungpook area. Obesity was defined as fat percentage that exceed 25% of body fat mass. Energy and nutritional status were tended to be low, and dietary intake of calcium and iron were less than any other nutrients in all the subjects. Especially, beverage intake of obese group was more than non-obese group. The leptin level were significantly correlated with %RDA of energy (0.41, p < 0.001), protein (0.44, p < 0.001), phosphate (0.40, p < 0.001), iron (0.37, p < 0.001), vitamin A (0.31, p < 0.01), thiamin (0.40, p < 0.001), riboflavin (0.26, p < 0.05), niacin (0.51, p < 0.001), and vitamin C (0.24, p < 0.05). The leptin level were significantly correlated with MAR (mean adequacy ratio, r : 0.43, p <0.001) and INQ (index of nutrient quality) of thiamin (r : 0.22, p <0.05). Multiple regression analysis showed that %RDA of niacin in obese group ($R^2$: 0.208, p : 0.001) and total subjects ($R^2$ : 0.257, p : 0.000), MAR (p : 0.003) and INQ (p : 0.048) of niacin in obese group ($R^2$ : 0.255) and MAR (p : 0.000) and rNQ ofca (p : 0.024) in total subjects ($R^2$ : 0.231) may be important independent predictors to leptin level. MAR showed a significantly positive correlation with %fat (r = 0.42, p < 0.01), BMI (r = 0.46, p < 0.01), RW (r : 0.44, p < 0.01), WHR (r : 0.39, p < 0.01) and, "ieRnA (p < 0.05, p < 0.01). These data indicated relationships among leptin level, nutrient intake, %RDA, MAh, and INQ in children.dren.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.662-675
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• 1998

The purpose of this study was to provide basic data on preschool children for accident prevention and to improve their health through a sound, safe living environment with safety education established through more systematic methods. Data were collected from 516 preschoolers from 4 to 6 years old using APP paper test which consists of a question and drawing. The children's general characteristics and accident proneness prospect were investigated. The relationship between the children's general characteristics and the accident proneness prospect were analyzed. The findings of the study are as follows : 1. The institution which children attended had a significant difference in accordance with the living safety (p=.015) and behavioral character(p=.033). 2. The housing pattern in which children lived had a significant difference in accordance with the movement speed(p=.027). 3. The children's age had a significant difference in accordance with the living safety(p=.002), traffic safety(p=.001), the reasoning power(p=.000), movement speed(p=.00), movement stability(p=.000) and attentional power(p=.000). 4. The children's sex had a significant difference in accordance with the movement stability and behavioral character (p=.003, p=.008). 5. The children's past accidental experience had a significant difference in accordance with the behavioral character(p=.001). 6. General assessment of the APP test had a significant difference in accordance with the children's age(p=.000) and children's past accidental experience(p=.020).

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.15-20
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• 1990

A laboratory experiment was conducted to investigate the relationship between the composition of phosphorus forms and soil chemical properties. The soil samples were collected from the farms of the 149 locations where vegetables were intensively cultivated with heavy application of phosphorus. The composition percentages of Ca-P and Saloid-P to the total phosphorus were increased as increasing soil pH while those of Fe-P and Al-P were decreased, The composition percentage of Fe-P were increased up to pH 5.0-6.0 and decreased as increasing pH above 6.0. respectively. The pH dependency of Al-P and Fe-P composition percentage was more remarkable for the soils with high available phosphorus (>500ppm) than with low available phosphorus (<500ppm). Composition percentages were in order of Fe-P>Al-P>Ca-P>Saloid-P for the soils with available phosphorus below 500ppm, while those were in order of Al-P>Fe-P>Ca-P>Saloid-P for the soils with high available phosphorus above 1,000ppm. Composition percentages of Al-P and Fe-P were increased as increasing active Al content, and Fe-P was increased as increasing of active Fe and P sorbed but saloid-P, Al-P and Ca-P were decreased.

• Journal of Internet Computing and Services
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• v.3 no.6
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• pp.25-33
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• 2002

The efficiency of the data share service of P2P method is decided by the maintaining guard method of a sharing list, This paper suggests the data sharing system of the P2P base that it should retain a shared data list at a client, The Server at a proposed system guards inclusively client. divided into several groups and at each individual group, a client appointed the TopHost uses the method guarding a free share list of a applicating group, The TopHost designs to execute it relating with server in case of the mergence and the division of a group as well as a maintaining management of a data share list, The efficiency of the suggested system regard the maintaining guard of groups formed of a client of the appropriate level of a kernel and exams examination to measure it through a really executed data share service.

• Journal of the Korean Mathematical Society
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• v.52 no.4
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• pp.751-763
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• 2015

Let ${\alpha}$ be a positive integer, and let $p_1$, $p_2$ be two distinct prime numbers with $p_1$ < $p_2$. By using elementary methods, we give two equivalent conditions of all even near-perfect numbers in the form $2^{\alpha}p_1p_2$ and $2^{\alpha}p_1^2p_2$, and obtain a lot of new near-perfect numbers which involve some special kinds of prime number pairs. One kind is exactly the new Mersenne conjecture's prime number pair. Another kind has the form $p_1=2^{{\alpha}+1}-1$ and $p_2={\frac{p^2_1+p_1+1}{3}}$, where the former is a Mersenne prime and the latter's behavior is very much like a Fermat number.

• Journal of Plant Biology
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• v.38 no.4
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• pp.365-371
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• 1995

Binary vectors, pBI-ActR1, pBI-ActF1 and pBSH-ActR1, were constructed using pGA642, the replication origin of pTi12 and the rice actin promoter. The sizes of pBI-ActR1, pBI-ActF1 and pBSH-ActR1 were 12.9 kb, 13.2 kb and 11.95 kb, respectively. These vectors containing a rice actin promoter followed by a GUS structural gene could induce stronly the expression of GUS gene in transformed rice cells. Rice explants from 3-4 day old seedlings after germinatin were cocultured with A. tumefaceins harboring pBI-ActR1, pBI-ActF1 or pBSH-ActR1, and then GUS expression in the explants was assayed. Transformation of rice explants by these binary vectors was tissue-specific, such that the meristematic regions of shoot apex, root and hypocotyl were transformed by these binary vectors.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.05a
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• pp.139-143
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• 2005

The P2P is a network environment supporting data exchange which is directly connected peers without limit of existing server-client and intervening central server for resource or offered service with each peer. JXTA is a representative of P2P system. JXTA is a typical distributed computing model that proposed by Sun Microsystems. JXTA that doesn't require centralized services or resources is adaptable in extreme changes of network organization. MANET(Mobile Ad Hoc Network) is a representative wireless network that is composed of mobile nodes without infrastructure. So MANET establishes the path for the communication of each peers and maintains the newest routing information by exchanging routing information. In this paper, we propose a technique of JXTAMAUET which implements JXTA which is the P2P network system from the wireless network which is becoming the foundation of ubiquitous computing. For the performance evaluation of the JXTAMANET, we use simulation.