• Title/Summary/Keyword: wound response

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Coating properties of PPG-based Polyurethane Dispersion wound covering resin by Addition of PVA (PVA의 첨가에 의한 PPG기반 수분산 창상피복수지의 코팅 물성)

  • Lee, Joo-Youb
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.1
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    • pp.178-185
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    • 2021
  • In this study, polyvinyl alcohol (PVA) and polypropylene glycol (PPG)-based polyurethane dispersion resin for wound coating was synthesized. And the physical properties of the sample were coated on the surface of the film sample and the leather (Full-Grain) to study the physical properties change. In the case of tensile strength, PUD-PA1, which reacted with the least amount of PVA, showed the highest resistance at 2.00 kgf/㎟. Likewise, the rate of elongation was measured as high as 554% for PUD-PA1, which reacted with the least amount of PVA. The abrasion resistance measurement result showed that as the PVA response increased, the strength of the surface decreased to 36.77 mg.loss.

The Effects of Pulsed Electromagnetic Energy and Microcurrent on Wound Healing in Rabbits. (맥동전자장에너지의 미세전류가 가토의 상처치유에 미치는 영향)

  • Kwon Won-An;Park Rae-Joon;Park Youn-Ki;Hwang Tae-Yeun
    • The Journal of Korean Physical Therapy
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    • v.12 no.3
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    • pp.319-329
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    • 2000
  • The purpose of this study w8s to evaluate the effects of pulsed electromagnetic energy(Diapulse) and microcurrent on the wound healing in rabbits. 15 domestic rabbits were randomly assigned to the PRME(n=5). MC(n=5) and CON(n=91 group. Each rabbits were anesthetized with lidocaine HCL $2\%$. Skin wounds were created laterally on the back of IS domestic rabbits(33cm). From 24 hours after being injured, the rabbits of the PEME group were irradiated with an intensity of 3 at a 300 pulses per second, which were applied for 15 minutes every day during the 12 days. The MC group were stimulated with an intensity of $50{\mu}A$ at frequency of40 pulses per second, which were applied for 15 minutes every day during the 12 days. The CON group were not stimulated. The rabbits were sacrificed and the incised wound pans were processed appropriately for the light microscopic examination on the 3rd day, 6th day and 12th day before the beginning of wound treatment. The areas of wound were measured with metric graph paper. The results were as tallows. 1 The PRME and MC group compared with control group showed that wound closure rate increased on 6th, 12th day. 2. It was found that the CON group did not show a complete maturation and had a chronic inflammatory response. Judging from the irregularity of intercellular space and the loose alignment of connective tissue. these findings showed that wound healing was delayed. 3. It showed that inflammatory cells. fibroblasts and epithelial cells activity rapidly processed in the PEME group compared with the CON group. It was found that the PEMI; group showed a advanced remodeling of epithelial layer and a positive repair of connective tissue. 4. It showed that fibroblasts, epithelial cells and inflammatory cells activity rapidly processed in the MC group compared with the CON group. It was found that the MC group showed a improved remodeling of epithelial layer and a dense connective tissue.

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Adaptive Control for Speed of Wound Rotor Induction Motor With Slip Energy Recovery

  • Tunyasrirut, Satean;Kanchanatep, Attapol;Ngamwiwit, Jongkol;Furuya, Tadayoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.419-422
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    • 1998
  • This paper presents how to design speed control of wound rotor induction motors with slip energy recovery. The speed is limited at some range of sub-synchronous speed of the rotating magnetic field. The problem with speed control by adjusting resistance value in the rotor circuit reduces the efficiency of power, because of the slip energy is lost when it passes through the rotor resistance. The control system is designed to maintain efficiency of motor, where it recovers loss energy by returning it to the system to improve the efficiency. A new PI control method of adaptive control [1],[13]is applied for the system with cascade type PI controller on the main loop to keep the speed constant and the internal loop to adjust the rotor appropriated current of the load provides the good transient response without overshoot.

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Harmonic Compensation by A Flywheel System Based on Stator Flux-Oriented Vector Control of WRIM(Wound Rotor Induction Machine) (권선형 유도전동기의 고정자 자속기준 벡터제어에 의한 전원선의 고조파 보상)

  • Kim Yoon-Ho;Cho Yong-Hyun;Park Kyung-Soo;Jeong Yeon-Suk
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.256-259
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    • 2001
  • An increase of pulsed power demand and load variation produce bad effect to power system. This causes power factor decrease. This paper proposes the excitation of the secondary side of wound rotor induction machine as one of harmonic compensation systems. In this paper, a harmonic compensation scheme based on stator flux-oriented vector control is proposed. By using the flux-oriented vector control, a voltage source PWM(Pulse Width Modulation) control scheme can be applied with fast dynamic response time. The designed control scheme is verified through simulation.

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AN EXPERIMENTAL STUDY OF TISSUE REACTION OF ABSORBABLE SUTURE MATERIALS (수종(數種)의 흡수성(吸收性) 봉합사(縫合絲)가 조직반응(組織反應)에 미치는 영향(影響)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Song, Sun-Chul;Kim, Kyung-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.13 no.4
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    • pp.381-390
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    • 1991
  • The purpose of this study was to select the absorbable suture material with the lowest level of foreign body reaction in the extraoral field. The absorbable sutures tested were polyglactin 910(Vicryl), polyglycolic acid(Dexon), and chromic gut. Black silk served as to control suture. Eighteen domestic rabbits served as the animal model for testing purposes. After shaving the fur, A six centimeter incision was made in the hind quarter of all eighteen animals. Each wound was then closed wit two Vicryl, two Dexon, and two chromic gut sutures. All wounds were closed in the same manner. A similar wound was made on the oppsite side and closed with black silk suture. Three rabbits were then sacrificed on postoperative day one, three, seven fourteen, twenty-one, and twenty-eight. The surgical sites were then examined histologically. 1. On days one, three, and seven all suture materials as a similar severe level of inflammatory response. On the fourteenth day the inflammatory reaction of Vicryl was minimal, chromic gut was moderate, and Dexon was severe, Black silk control groups demosnstrated the most severe levels of inflammation of all sutures tested from day fourteen to twenty-eight. 2. On the fourteenth day all absorbable suture materials demonstrated similar minimal levels of resorption. At twenty-eight days Vicryl demonstrated a greater amount of resorption than Dexon or cromic gut suture. There was no resorption noted in the black silk control groups through day twenty-eight. 3. Due to its decreased level of inflammatory response in the animal model, Vicryl might be expected to as a decreased level of response in humans. It is felt that Vicryl is preferred to Dexon or chromic gut for extraoral suturing.

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Energy Storage And Power Compensation Based on Flywheel WRIM System (플라이휠 유도전동기 시스템을 이용한 에너지 저장 및 전력보상)

  • 김윤호;이경훈;박경수
    • Journal of the Korean Society for Railway
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    • v.2 no.4
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    • pp.32-39
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    • 1999
  • A flywheel system which can compensate electric power is presented. The designed system has a capability of providing real and imaginary power instantaneously as well as storing energy. In this paper, a control algorithm is designed. The designed algorithm is to control the secondary side current of the wound rotor induction motor using voltage-based PWM inverter. The flywheel system has advantages in converter size and power quality improvement comparing to the conventional system.

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Digital Time-Domain Simulation of Ferroresonance of Potential Transformer in the 154 kV GAS Insulated Substation

  • Shim, Eung-Bo;Woo, Jung-Wook;Han, Sang-Ok
    • KIEE International Transactions on Power Engineering
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    • v.11A no.4
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    • pp.9-14
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    • 2001
  • This paper reports a set of digital time-domain simulation studies conducted on 154 kV wound Potential Transformer(PT) int he 154 kV Gas Insulated Substation(GIS). The Electro-Magnetic Transient Program(EMTP) is used to develop the PT model and conduct the transient studies. The accuracy of the PT model is verified through comparison of the EMTP simulation results with those obtained from the field test results. The investigations shows that the developed model can accurately predict PT transient resonance, especially, the phenomenon of ferroresonance. The model is developed not only to determine impact of transients on PT response but also to design ferroresonance suppressor devices of PT. And it can also be used to predict PT transient response on power system monitoring and protection scheme.

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GUS Expression Driven by Promoter of AtSAGT1 Gene Encoding a Salicylic Acid Glucosyltransferase 1 in Arabidopsis Plants

  • Sendon, Pamella Marie;Park, Jong-Beum;Park, Soon-Ki;Song, Jong Tae
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.2
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    • pp.83-87
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    • 2013
  • AtSAGT1 encodes a salicylic acid (SA) glucosyltransferase enzyme that catalyzes the formation of SA glucoside and SA glucose ester. Here, the AtSAGT1 gene expression patterns were determined in AtSAGT1 promoter::GUS transgenic Arabidopsis plants. As a result, the factors regulating the induction of AtSAGT1 were identified as pathogen defense response, wound response, exogenous application of SA, and jasmonic acid treatment.

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Cellular senescence: a promising strategy for cancer therapy

  • Lee, Seongju;Lee, Jae-Seon
    • BMB Reports
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    • v.52 no.1
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    • pp.35-41
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    • 2019
  • Cellular senescence, a permanent state of cell cycle arrest, is believed to have originally evolved to limit the proliferation of old or damaged cells. However, it has been recently shown that cellular senescence is a physiological and pathological program contributing to embryogenesis, immune response, and wound repair, as well as aging and age-related diseases. Unlike replicative senescence associated with telomere attrition, premature senescence rapidly occurs in response to various intrinsic and extrinsic insults. Thus, cellular senescence has also been considered suppressive mechanism of tumorigenesis. Current studies have revealed that therapy-induced senescence (TIS), a type of senescence caused by traditional cancer therapy, could play a critical role in cancer treatment. In this review, we outline the key features and the molecular pathways of cellular senescence. Better understanding of cellular senescence will provide insights into the development of powerful strategies to control cellular senescence for therapeutic benefit. Lastly, we discuss existing strategies for the induction of cancer cell senescence to improve efficacy of anticancer therapy.

Context-Dependent Regulation of Type17 Immunity by Microbiota at the Intestinal Barrier

  • Begum Akuzum;June-Yong Lee
    • IMMUNE NETWORK
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    • v.22 no.6
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    • pp.46.1-46.25
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    • 2022
  • T-helper-17 (Th17) cells and related IL-17-producing (type17) lymphocytes are abundant at the epithelial barrier. In response to bacterial and fungal infection, the signature cytokines IL-17A/F and IL-22 mediate the antimicrobial immune response and contribute to wound healing of injured tissues. Despite their protective function, type17 lymphocytes are also responsible for various chronic inflammatory disorders, including inflammatory bowel disease (IBD) and colitis associated cancer (CAC). A deeper understanding of type17 regulatory mechanisms could ultimately lead to the discovery of therapeutic strategies for the treatment of chronic inflammatory disorders and the prevention of cancer. In this review, we discuss the current understanding of the development and function of type17 immune cells at the intestinal barrier, focusing on the impact of microbiota-immune interactions on intestinal barrier homeostasis and disease etiology.