• Archives of Plastic Surgery
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• v.33 no.6
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• pp.742-747
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• 2006

Purpose: The purpose of this study was to evaluate the role of mast cell and histamine as typical product of mast cell in ischemia-reperfusion injury of muscle flap using H2 receptor blocker and mast cell stabilizer. Methods: Thirty-five Sprague-Dawley rats weighing 250-300 gm were divided into four groups; Group I: Control group without ischemia, Group II: Normal saline injection group with ischemia, Group III: Cimetidine injection group with ischemia, Group IV: Sodium cromoglycate injection group with ischemia. Well established single pedicled transverse rectus abdominis musculocutaneous(TRAM) flap was designed in all rats and were rendered ischemia by clamping the artery for 150 minutes. All injections were applied intramuscular around gluteal area 30 minutes before reperfusion. The flap survival was evaluated at 7 days after operation. Neutrophil counts and mast cell counts were evaluated 24 hours after reperfusion. Results: The difference of skin flap survival between control group and cimetidine injection group was not significant. In the normal saline injection group flap survival was markedly decreased compared to that of control group. The muscle flap survival was similar to the results of skin flap survival. The neutrophil counts were significantly decreased in control group and sodium cromoglycate injection group than normal saline injection group. The mast cell counts were significantly decreased in cimetidine injection group and control group than both normal saline injection and sodium cromoglycate injection groups. The protective effect of sodium cromoglycate was not seen in the skin flap, but the muscle flaps showed protective effects of sodium cromoglycate compared to normal saline injection group. Conclusions: It is suggests that commonly used antihistamine(H2 receptor blocker) has protective effect against ischemia-reperfusion injury to skin and muscle flaps by reducing neutrophil and mast cell. The mast cell stabilizer was not effective for skin flap but, possibly, for muscle flap.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.16 no.3
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• pp.220-229
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• 2003

Background and Objectives : The diagnosis of allergic diseases in current oriental medicine is in the state of depending mainly on two factors: some distinctive symptoms and scientific 'opinions', MAST CLA test is also believed to be helpful in Oriental Medicine on making definite diagnosis of allergic diseases and identifying causative antigen. This study will address the clinical importance of MAST CLA test, the residential type of allergic patients and its distribution status, etc. Methods : From March of 2000 through September of 2003, tests were made in Oriental Medicine Hospital of Semyung University on sex, age, types of residence, allergic diseases and MAST CLA system for the patients who showed allergic symptoms and had been diagnosed so in other hospitals. Results : 1. Sex: Among 91 subjects, 38 of them were men, 53 of them were women. 2. Age group : 15.3% of them were in their 40s; 31.8% in 30s; 15.3% in 20s; 17.5% in 10s. 3. Residental type : A.P.T(51 of them, 56%), plain type of house(33 of them, 36.2%) and villa(7 of them, 7.6%). 4. Discases : Among the diseases, allergic dermatitis was most common(69 of them. 75.8%); allergic rhinitis(17 of them, 18.6%); and chronic and acute urticaria(4 of them, 4.3%) in order. 5. Among 91 subjects, 39 of them showed positive reaction to more than one type of antigens in MAST CLA test: 23 of them were men(60.5%); 16 of them. women(30.1%). 6. Among 91 subjects. 53 of them(58.2%) showed positive reaction to antibodies in MAST CLA test: 22 of them were men; 31 of them, women. 7. Antigen distribution order among 39 subjects who showed positive reaction in MAST CLA test: Mite-farinae, Mite-pterony, Housedust in men and women subjects alike.

• Journal of Ocean Engineering and Technology
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• v.33 no.1
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• pp.50-60
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• 2019

Recently, problems with excessive vibration of the radar masts of large bulk carriers and crude oil tankers have frequently been reported. This paper explores a design method to avoid the resonance of a radar mast installed on a large ship using various design of experiment (DOE) methods. A local vibration test was performed during an actual sea trial to determine the excitation sources of the vibration related to the resonant frequency of the radar mast. DOE methods such as the orthogonal array (OA) and Latin hypercube design (LHD) methods were used to analyze the Pareto effects on the radar mast vibration. In these DOE methods, the main vibration performances such as the natural frequency and weight of the radar mast were set as responses, while the shape and thickness of the main structural members of the radar mast were set as design factors. From the DOE-based Pareto effect results, we selected the significant structural members with the greatest influence on the vibration characteristics of the radar mast. Full factorial design (FFD) was applied to verify the Pareto effect results of the OA and LHD methods. The design of the main structural members of the radar mast to avoid resonance was reviewed, and a normal mode analysis was performed for each design using the finite element method. Based on the results of this normal mode analysis, we selected a design case that could avoid the resonance from the major excitation sources. In addition, a modal test was performed on the determined design to verify the normal mode analysis results.

• Wind and Structures
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• v.10 no.4
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• pp.347-366
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• 2007

Guyed masts subjected to turbulent winds exhibit complex vibrations featuring many vibration modes, each of which contributes to various structural responses in differing degrees. This dynamic behaviour is further complicated by nonlinear guy cable properties. While previous studies have indicated that conventional frequency domain methods can reliably reproduce load effects within the mast, the system linearization required to perform such an analysis makes it difficult to relate these results directly to corresponding guy forces. As a result, the estimation of peak load effects arising jointly from the structural action of the mast and guys, such as leg loads produced as a result of guy reactions and mast bending moments, is uncertain. A numerical study was therefore undertaken to study peak load effects in a 295 m tall guyed mast acted on by simulated turbulent wind. Responses calculated explicitly from nonlinear time domain finite element analyses were compared with approximate methods in the frequency domain for estimating peak values of selected responses, including guy tension, mast axial loads and mast leg loads. It was found that these peak dynamic load effects could be accurately estimated from frequency domain analysis results by employing simple, slightly conservative assumptions regarding the correlation of related effects.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.189-198
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• 2015

Background: Antiallergic effect of 20(S)-protopanaxatriol (PPT), an intestinal metabolite of ginseng saponins, was investigated in guinea pig lung mast cells and mouse bone marrow-derived mast cells activated by a specific antigen/antibody reaction. Methods: Increasing concentrations of PPT were pretreated 5 min prior to antigen stimulation, and various inflammatory mediator releases and their relevant cellular signaling events were measured in those cells. Results: PPT dose-dependently reduced the release of histamine and leukotrienes in both types of mast cells. Especially, in activated bone marrow-derived mast cells, PPT inhibited the expression of Syk protein, cytokine mRNA, cyclooxygenase-1/2, and phospholipase $A_2$ ($PLA_2$), as well as the activities of various protein kinase C isoforms, mitogen-activated protein kinases, $PLA_2$, and transcription factors (nuclear factor-${\kappa}B$ and activator protein-1). Conclusion: PPT reduces the release of inflammatory mediators via inhibiting multiple cellular signaling pathways comprising the $Ca^{2+}$ influx, protein kinase C, and $PLA_2$, which are propagated by Syk activation upon allergic stimulation of mast cells.

• Korean Journal of Medicinal Crop Science
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• v.16 no.1
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• pp.27-32
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• 2008

This study aimed to investigate the anti-allergic activity and the mechanism of action of Crassirhizomae rhizoma (CR). The extract of CR exhibited potent inhibitory activity in mast cells; its $IC_{50}$ values were $31.2{\pm}1.5{\mu}g/m{\ell}$ for rat basophile leukemia (RBL)-2H3 mast cells and $51.5{\pm}2.1{\mu}g/m{\ell}$ for bone marrow-derived mast cells by antigen stimulation. It also suppressed the expression of TNF-${\alpha}$ and IL-4 mRNAs in RBL-2H3 cells. In an in-vivo animal allergy model, it inhibited a local allergic reaction, passive cutaneous anaphylaxis (PCA), in a dose-dependent manner. With regard to the mechanism of action, CR inhibited the activating phosphorylation of Syk kinase, a key signaling protein for the activation of mast cells. Taken together, these results strongly suggested that the anti-allergic activity of CR is mediated through the inhibition of histamine release and allergic cytokine production by the inhibition of Syk in mast cells.

• Journal of the Korean Solar Energy Society
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• v.31 no.3
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• pp.1-7
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• 2011

In the performance test for wind turbines of medium and large, The reference met-mast should be installed for measurement reference wind speed as IEC 61400-12-1 standards and design of booms for mounted an anemometer must be considered exactly. Boom-mounted cup anemometer are influenced by flow distortion of the mast and the boom. Therefore design of booms must be important so that flow distortion due to booms should be kept below 0.5%. But, in some cases at size of met-mast structure, the distance of boom from mast is longer then measurement of wind speed is impossible because of oscillation of boom-mounted anemometer. In this paper, We measured a wind speed at several point from mast and boom and we analyzed the error of wind speed at each point of measurement. Also, we will suggest a correction method using the data curve fitting about errors of wind speed between each point of mounted anemometer.

• Journal of Oriental Neuropsychiatry
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• v.22 no.1
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• pp.37-51
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• 2011

Objectives : This experiment was designed to investigate the effect of Gamisoyo-san(Jiaweixiaoyaosan, SYS) on serotonin activity of P815 Mast Cell. Methods : The effects of SYS on activation of TPH-1 mRNA and AAADC mRNA in P815 mast cell were investigated. The effect of SYS on content of serotonin in P815 mast cell was investigated. The effects of SYS on activation of DPPH and SOD in P815 mast cell were investigated. Results : 1. The SYS increased the activation of SOD and DPPH in P815 mast cell. 2. The SYS decreased the manifestation TPH-1 mRNA in P815 mast cell. 3. The SYS decreased the manifestation AAADC mRNA in P815 mast cell. Conclusions : This experiment shows that Gamisoyo-san might not be effective for treating depression in terms of biogenic amine theory. However, Gamisoyo-san showed significant anti-oxidative effect and it can not yet be ruled out for treating depression. Therefore, pathogenesis of depression and clinical research of Gamisoyo-san is suggested for future research.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.480-484
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• 2001

본 연구에서는 실제 풍력 자원 측정용 Pole에 설치된 풍속계가 mast에 의한 후류와 풍속계 설치시 기울어짐에 의해 풍속 data가 어떠한 영향을 받는가에 대하여 고찰하였다. 먼저 mast은 직경 4", 6" Pipe에 대하여 각각 실험하였고, 측정 mast의 방위각은 풍속에 평행한 방향을 $0^{\circ}$ 로 정하고 측정 mast 중심으로부터 $0^{\circ}{\sim}20^{\circ}$ 까지 $5^{\circ}$ 간격으로 측정하였다. 이 연구를 통해 실제 일정 두께를 갖는 mast에 설치되어 있는 풍속계에서의 풍속이 풍향에 대한 boom의 위치와 기울어짐에 따라 영향이 있음을 확인할 수 있었고, mast의 직경에 대한 영향도 크게 있음을 확인할 수 있었다. 따라서, 본 연구의 결과를 이용하여 향후의 풍력자원 자료 측정설비의 설치상의 정확도 검증이나 혹은 측정된 자료의 보정등에도 광범위하게 이용될 수 있을 것이다.

• Journal of Drive and Control
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• v.16 no.3
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• pp.1-7
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• 2019

The reach truck, which is mainly used in warehouses, is required to have high-mast to improve its working efficiency and space utilization. The high-mast takes advantage of more vertical space but severe vibrations are easily generated at the end of the high-mast. These vibrations may cause a collision or misplacement of loading location at work. In this study, the vibration characteristics of a three-stage high-mast of a reach truck are analyzed, and an active vibration controller verified through a similar experiment is designed to reduce this vibration. A similar experiment for reach truck mast verifies the performance of the active vibration controller. By applying an active vibration controller designed for a real reach truck, the operations of the reach truck are made more efficient through the reduction of the vibration amplitude.