• Journal of Microbiology
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• v.42 no.4
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• pp.346-352
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• 2004

Poly(3-Hydroxybutyrate-co­3-Hydroxyvalerate), poly(3HB-co-3HV), copolyesters with a variety of 3HV contents (ranging from 17 to $60\;mol\%$) were produced by Alcaligenes sp. MT-16 grown on a medium containing glucose and levulinic acid in various ratios, and the effects of hydrophilicity and crystallinity on the degradability of the copolyesters were evaluated. Measurements of thermo-mechanical pro­perties and Fourier-transform infrared spectroscopy in the attenuated total reflectance revealed that the hydrophilicity and crystallinity of poly(3HB-co-3HV) copolyesters decreased as 3HV content in the copolyester increased. When the prepared copolyester film samples were non-enzymatically hydrolysed in 0.01 N NaOH solution, the weights of all samples were found to have undergone no changes over a period of 20 weeks. In contrast, the copolyester film samples were degraded by the action of extra­cellular polyhydroxybutyrate depolymerase from Emericellopsis minima W2. The overall rate of weight loss was higher in the films containing higher amounts of 3HV, suggesting that the enzymatic degra­dation of the copolyester is more dependent on the crystallinity of the copolyester than on its hydro­philicity. Our results suggest that the degradability characteristics of poly(3HB-co-3HV) copolyesters, as well as their thermo-mechanical properties, are greatly influenced by the 3HV content in the copoly­esters.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.95-102
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• 2005

The term pharmacognosy as applied to a constituent scientific discipline of Korean Medical Food (KMF) has been in use for nearly several years, and it refers to studies on the pharmacological properties of natural products foods. During the last half of the 20th century, pharmacognosy for KMF evolved from being a descriptive botanical subject to one having a more chemical and biological focus. At the beginning of the 21st century, teaching pharmacognosy for KMF teaching in academic culinary arts and natural healing institutions has been given new relevance as a result of the explosive growth in the use of herbal foods (health foods) in modern KMF practice. In turn, pharmacognosy for KMF research areas are continuing to expand, and now include aspects of cellular and molecular biology in relation to natural products, ethnobotany and phytotherapy, in addition to the more traditional analytical method development and phytochemistry. Examples are provided in this review of promising bioactive compounds obtained in two multidisciplinary natural product KMF development and discovery projects, aimed at the elucidation of new plant-derived cancer chemotherapeutic agents and novel cancer chemopreventives, respectively. The systematic study of KMF offers pharmacognosy groups an attractive new area of research, ranging from investigating the biologically active principles of KMF and their mode of action and potential active substance interactions, to sanitary and quality control, and involvement in clinical trials.

• Biomolecules & Therapeutics
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• v.23 no.3
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• pp.245-250
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• 2015

Silibinin, a natural flavonoid antioxidant isolated from extracts of the milk thistle herb, has recently been identified as having anti-hepatotoxic and anticancer properties. In this paper, we investigated the effects of silibinin on behavior and neuroplasticity in mice subjected to chronic unpredictable mild stress (CUMS). After 5 consecutive weeks of CUMS, the mice were treated with silibinin (100 mg/kg, 200 mg/kg and 400 mg/kg by oral gavage) for 3 consecutive weeks. The results showed that silibinin administration significantly alleviated the CUMS-induced depressive-like behavior, including the total number of squares crossed and the frequency of rearing in the open field test, the immobility time in the tail suspension test and the forced swimming test. Furthermore, silibinin treatment increased the levels of brain-derived neurotrophic factor (BDNF), serotonin (5-HT) and norepinephrine (NE) in the prefrontal cortex and hippocampus. Our study provides new insight into the protective effects of silibinin on the depressive status of CUMS mice, specifically by improving neuroplasticity and neurotransmission.

• International Journal of Concrete Structures and Materials
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• v.18 no.1E
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• pp.29-34
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• 2006

Elastic modulus, tensile and bond capacities are important factors for developing an effective reinforcing action of a flexural member as a reinforcing material for concrete structures. Reinforcement must have enough bond capacity to prevent the relative slip between concrete and reinforcement. This paper presents an experimental study to clarify the bond capacity of prestressed carbon fiber reinforced polymer(CFRP) rod manufactured by an automatic assembly robot. The bond characteristics of CFRP rods with different pitch of helical wrapping were analyzed experimentally. As the result, all types of CFRP rods show a high initial stiffness and good ductility. The mechanical properties of helical wrapping of the CFRP rods have an important effect on the bond of these rods to concrete after the bond stress reached the yield point. The stress-slip relationship analyzed from the pull-out test of embedded cables within concrete was linear up to maximum bond capacity. The deformation within the range of maximum force seems very low and was reached after approximately 1 mm. The average bond capacity of CF20, CF30 and CF40 was about 12.06 MPa, 12.68 MPa and 12.30 MPa, respectively. It was found that helical wrapping was sufficient to yield bond strengths comparable to that of steel bars.

• Korean Journal of Plant Resources
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• v.25 no.6
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• pp.664-669
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• 2012

The mushroom Coriolusversicolor contains biologically active polysaccharides, most of which belong to the ${\beta}$ glucan group. Diverse physicochemical properties, due to different sources and isolated types of ${\beta}$-glucans, may induce distinct biological activities. Here, we examined the effects of ${\beta}$-glucan from Coriolusversicolor (CVG) on the scavenger receptor B1 (SR-B1) expression and the role of SR-B1 in CVG-induced phagocytosis regulation by using SR-B1-specific shRNA transfected cells. We also examined whether Dectin-1 and CK2 are involved in SR-B1 expression in CVG-treated cells. Our study results showed that CVG increased the SR-B1 expression via Dectin-1 and CK2 in macrophages. However, the inhibition of SR-B1 expression by shRNA did not completely eliminate the effect of CVG on the increase of phagocytosis suggesting that SR-B1 is not essential for CVG-stimulated phagocytosis. This study will contribute to identify CVG's mechanism of action and its use in the development of functional foods.

• Structural Engineering and Mechanics
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• v.41 no.2
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• pp.231-242
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• 2012

This research work aims to develop an optimal design using Finite Element (FE) and Genetic Algorithm (GA) methods to replace the traditional concrete and timber material by a Synthetic Polyurethane fibre glass composite material in railway sleepers. The conventional timber railway sleeper technology is associated with several technical problems related to its durability and ability to resist cutting and abrading action of the bearing plate. The use of pre-stress concrete sleeper in railway industry has many disadvantages related to the concrete material behaviour to resist dynamic stress that may lead to a significant mechanical damage with feasible fissures and cracks. Scientific researchers have recently developed a new composite material such as Glass Fibre Reinforced Polyurethane (GFRP) foam to replace the conventional one. The mechanical properties of these materials are reliable enough to help solving structural problems such as durability, light weight, long life span (50-60 years), less water absorption, provide electric insulation, excellent resistance of fatigue and ability to recycle. This paper suggests appropriate sleeper design to reduce the volume of the material. The design optimization shows that the sleeper length is more sensitive to the loading type than the other parameters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.433-436
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• 2012

Today due to the development of technology, 3D graphics have become an essential element of the game graphic. When game companies create a game using 3D graphics, game users can enjoy a better game graphics like photo-realistic live action than 2D game graphics. And because the game companies have many advantages in creating games which are easy to deal with many basic effects and special effects, in video game business field, 3D game have become the mainstream. This paper will inquire the characteristics of 2D spline which is basic to various kinds of 3D modeling necessary to making 3D game graphics, compare and analyze the merits and demerits of each kind of spline and find out its development history.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.12
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• pp.1155-1163
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• 2004

Extracellular signal-regulated kinase (ERK) signaling pathway is one of the mitogen-activated protein kinase (MAPK) signal transduction pathways. This pathway is known as pivotal in many signaling networks that govern proliferation, differentiation and cell survival. The ERK signaling pathway comprises positive and negative feedback loops, depending on whether the terminal kinase stimulates or inhibits the activation of the initial level. In this paper, we attempt to model the ERK pathway by considering both of the positive and negative feedback mechanisms based on Michaelis-Menten kinetics. In addition, we propose a fraction ratio model based on the mass action law. We first develop a mathematical model of the ERK pathway with fraction ratios. Secondly, we analyze the dynamical properties of the fraction ratio model based on simulation studies. Furthermore, we propose a concept of an inhibitor, catalyst, and substrate (ICS) controller which regulates the inhibitor, catalyst, and substrate concentrations of the ERK signal transduction pathway. The ICS controller can be designed through dynamical analysis of the ERK signaling transduction pathway within limited concentration ranges.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.590-595
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• 2008

In the present paper, the impact damage behavior of steel plate reinforced concrete panels exposed to shock impulsive loading and fragment impact loading is investigated. To evaluate the retrofit performance of a steel-strengthened concrete panels, a numerical experiment using a numerical simulation with AUTODYN, an explicit analysis program is introduced because a real explosion experiment requires the vast investment and expense for facilities as well as the deformation mechanisms are too complicated to be reproduced with a conventional closed-form analyses. The model for the analysis is simplified and idealized as a two-dimensional and axisymmetric case controled with geometry, boundary condition and material properties in order to obtain a resonable computation time. As a result of the analysis, panels subject to either shock loading or fragment loading without the steel plate reinforcement experience the perforation with spalled fragments. In addition, the panels reinforced with steel plate can prevent the perforation and provide the good mechanical effect such as the increase of global stiffness and strength through the composite action between the concrete slab and the steel plate.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3569-3573
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• 2013

Aim: Pendulous monkshood root is traditionally used for the treatment of several inflammatory pathologies such as rheumatisms, wounds, pain and tumors in China. In this study, the anti-inflammatory and anticancer activities and the mechanism of crude ethanol extract of pendulous monkshood root (EPMR) were evaluated and investigated in vitro. Materials and Methods: The cytotoxic effects of EPMR on different tumor cell lines were determined by the MTT method. Cell apoptosis and cell nucleus morphology were assessed by Hoechst 33258 staining. Moreover, nitric oxide (NO) levels and intracellular oxidative stress in peritoneal macrophages were determined to further elucidate mechanisms of action. Results: The data showed that EPMR could produce significant dose-dependent toxicity on three kinds of tumor cells. Furthermore, EPMR displayed obvious anti-inflammatory effects on LPS-induced mouse peritoneal macrophages at the dosage of 4 - 200 ${\mu}g/mL$. The results demonstrated the therapeutic potential of Pendulous Monkshood Root on cancer and inflammatory diseases. Conclusion: Our results indicate that EPMR has anti-inflammatory and anticancer properties, suggesting that pendulous monkshood root may be a useful anti-tumor and anti-inflammatory reagent in the clinic.