• IMMUNE NETWORK
• /
• v.14 no.2
• /
• pp.107-115
• /
• 2014

Phellinus linteus has been used as a traditional herbal medicine in Asian countries and is known to have anti-tumor, immunomodulatory, anti-inflammatory, and anti-allergic activities. However, the protective effects of P. linteus against experimental asthma have not been fully investigated. The objective of this study was to determine whether P. linteus ethanol extract (PLE) suppresses inflammatory response in an OVA-induced asthma model. As expected, the oral administration of PLE significantly inhibited eosinophilic airway inflammation and airway hyperresponsiveness in OVA-challenged BALB/c mice. Supporting these data, the augmentation of Th2 cytokines (IL-4, IL-5, and IL-13), eotaxin, and adhesion molecules in lung tissues and bronchoalveolar lavage fluid after OVA inhalation was markedly attenuated by PLE. Furthermore, PLE reduced OVA-induced activation of NF-${\kappa}B$ and p38 MAPK in lung tissues. Therefore, our results suggest the potential of P. linteus as a therapeutic agent for asthma.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.26 no.10
• /
• pp.2180-2186
• /
• 2002

In a micro-scale contact, capillary force and van der Waals interaction significantly influence the contact between asperities of rough surfaces. Little is, however, known about the variation of these surface forces as a function of chemical property of the surface (wet angle), relative humidity and deformation of asperities in the real area of contact. A better understanding of these surface forces is of great necessity in order to find a solution for reducing friction and adhesion of micro surfaces. The objective of this study is to investigate the surface forces in micro-scale rough surface contact. We proposed an effective method to analyze capillary and van der Waals forces in micro-scale contact. In this method, Winkler spring model was employed to analyze the contact of rough surfaces that were obtained from atomic force microscopy (AFM) height images. Self-mated contact of DLC(diamond like carbon) coatings was analyzed, as an example, by the proposed model. It was shown that the capillary force was significantly influenced by relative humidity and wet angle of the DLC surface. The deformation of asperities to a critical magnitude by external loading led to a considerable increase of both capillary and van der Waals forces.

• Journal of Lipid and Atherosclerosis
• /
• v.7 no.2
• /
• pp.88-97
• /
• 2018

The prevalence of atherothrombotic disease continues to rise, presenting an increasing number of challenges to modern society and creating interest in functional foods. Platelet activation, adhesion, and aggregation at vascular endothelial disruption sites are key events in atherothrombotic disease. Physiological challenges such as hyperlipidemia, obesity, and cigarette smoking are associated with vascular changes underlying platelet aggregation and inflammatory processes. However, it is difficult to determine the beneficial response of functional foods in healthy subjects. To address this problem, challenge models and high-risk models related to smokers, obesity, and dyslipidemia are proposed as sensitive measures to evaluate the effects of functional foods in healthy subjects. In this review, we construct a model to evaluate the effects of functional food such as natural products on blood flow based on a human intervention study.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.724-730
• /
• 2011

A turnout serves to switch train from one line to another. The turnout consists of a Point which is switchs the rail to induce direction, and a Crossing which is cross over two line on the plane surface, and a Lead where is middle section in Point to Crossing. Point machine, consists of a turnout, is important facilities in railway signal, that is safety issue relates in derailment of the train. Recently, train delay and accident frequently occurred because of the turnout include in a point machine trouble of electrical and mechanical. So in order to prevent train accident the research is advanced, install of normal and reverse indication lamp in a point machine, development of adherence detector for sensing the status of adhesion between the stock rails and tongue rails etc. In this paper investigates the problem which is connected with a turnout trouble, include in a point machine, occurrence at the time of train accident, and then proposed to the safety system model in order to prevent the train accident in turnout.

• Journal of the Korean Society for Heat Treatment
• /
• v.15 no.5
• /
• pp.228-233
• /
• 2002

The characteristics of the induction heating process are analyzed for the joint of nylon and metal. The temperature of metal surface is measured using thermocouples. The relations of temperature and induction heating parameters are analyzed. Heat equation models are constructed and the temperature distribution is predicted using Fluent. The effects of heating parameters on the joint strength are evaluated. Finally, the optimal parameters of induction heating process are proposed as 16kW and 6 seconds.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.10
• /
• pp.1005-1013
• /
• 2009

In this paper, the performance improvement of a decentralized brake system for railway rolling stocks is investigated. In order to verify the effectiveness of the decentralized brake system, it is compared to the truck unit brake system which has only one control unit per a truck. The adaptive sliding mode control scheme is used to realize a robust anti-slip brake control system. Through computer simulations, it is verified that the decentralized brake system has better braking performance than the truck unit brake system.

• Reproductive and Developmental Biology
• /
• v.38 no.1
• /
• pp.35-40
• /
• 2014

Beta-catenin (CTNNB1, catenin (cadherin-associated protein), beta 1) is involved in various biological processes, including embryogenesis, tumorigenesis, angiogenesis and progression of metastasis. CTNNB1, as a multifunctional and oncogenic protein, has important roles in adhesion between Sertoli cells through an N-cadherin-dependent manner and in various cancer types through its over-activation. In addition, CTNNB1 can interact with estrogen/estrogen receptor alpha complex, which regulates the transcription of WNT (wingless-type MMTV integration site family)/CTNNB1 target genes. Recently, we investigated the functional roles and expression pattern of CTNNB1 during the morphological changes of embryonic gonads of chickens and the estrogen-dependent regulation of CTNNB1 in oviduct development and potential functions as a biomarker of CTNNB1 in human epithelial ovarian cancer using the chicken as a biological research model. Therefore, in this review, we provide a new insight of potential role of CTNNB1 in the development of the female reproductive tract during early embryogenesis and ovarian carcinogenesis of laying hen models.

• Journal of the Korean Applied Science and Technology
• /
• v.29 no.2
• /
• pp.286-294
• /
• 2012

This study is a review paper on powders for makeup cosmetics. They play the roles of the camouflage of skin defect, UV screening, skin adhesion, makeup sustainability, and skin protection. This function is endowed on the powders by shape control, surface treatment, and encapsulation. The future powders are expected to be evolved into the smart model responding to the environmental change.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.340-340
• /
• 2006

Applying force-distance curve measurement by atomic force microscopy to a theoretical mechanical model gives us elastic properties of polymer surfaces. Our group focuses on force-mapping method, in which force-distance curve is performed at each lattice point on a sample surface and subsequently a variety of properties derived from analytical results are combined to construct a 2-dimensional image. With this method we succeeded in deriving Young' s modulus distribution map method of rubbery/rubbery polymer blend surfaces with ${\sim}100\;nm$ lateral resolution. We also applied force-mapping method to another theory to divide distribution of hardness from that of adhesion. We will demonstrate recent progress.

• Tribology and Lubricants
• /
• v.30 no.1
• /
• pp.36-45
• /
• 2014

Understanding steel/skin contact phenomena is important for the study of object manipulation in robotics and has been a topic of great interest. In this study, pig skin was taken as a surrogate model for human skin, and its adhesive, friction, and deformation behaviors were measured under various exposure times to air. Indentation, friction, and scratch tests were performed at $25^{\circ}C$ and 45% relative humidity. The influences of adhesion and deformation on the coefficient of friction were characterized; the pig skin was found to be sensitive to the sliding velocity and normal load under the controlled experimental conditions.