• Title/Summary/Keyword: Beating Rate

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Effects of Myrrha Water Extract on Rat Myocardial Cells in Cultures (몰약 전탕액이 배양 심근세포에 미치는 영향)

  • 권강범;조현익;김구환;김상범;이호섭;황우준;박승택;류도곤
    • The Journal of Korean Medicine
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    • v.21 no.2
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    • pp.79-86
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    • 2000
  • Objectives and Methods : In order to elucidate toxic mechanism of myocardial damage and protective effect of myrrha water extract against cytotoxic effect of xanthine oxidase/hypoxanthine(XO/HX), cardioprotective effect of myrrha water extract was examined by MTT assay, LDH (Lactate Dehydrogenase) activity and heart beating rate after cultured myocardial cells derived from neonatal mouse were treated with various concentration of XO/HX, a free radical. Results : XO/HX induced a decrease of cell viability, an increase in the amount of LDH, and a decrease of heart beating rate on cultured myocardial cells in a dose-dependent manner. In cardioprotective effect of myrrha water extract, it showed a decrease in the amount of LDH and an increase of heart beating rate on cultured myocardial cells damaged by XO/HX. Conclusions : From the above results, it is suggested that XO/HX showed toxic effect in cultured myocardial cells derived from neonatal mouse and that myrrha water extract is very effective in the prevention of XO/HX-induced cardiotoxicity.

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Deterioration Mechanism of Paper According to Sizing and Beating (II) -Influences of Beating- (사이징과 고해에 따른 종이의 열화기구(제2보) -고해의 영향-)

  • 김봉용
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.2
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    • pp.58-63
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    • 1999
  • Three kinds of papers were prepared from different beating degree of pulps. Physical and optical properties were examined to elucidate the deterioration mechanism of paper according to beating degrees. Changes of double folds, elongation, water retention value, DP, K/S value and visible, UV region light absorption spectra of those papers treated by UV light were studied. Double folds and brightness were decreased more rapidly by UV treatment with increasing of beating degree. The light absorption rates of pulps in visible and UV region were also increased with change of beating level. The formation of new hydrogen bonds and higher light absorption rate of pulps according to beating induced to absorb and interact with much UV light. These phenomena maybe brought about to accelerate paper deteriortion by UV treatment both optical and physical properties.

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Beating phenomena in spacecraft sine testing and an attempt to include the sine sweep rate effect in the test-prediction

  • Nali, Pietro;Bettacchioli, Alain
    • Advances in aircraft and spacecraft science
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    • v.3 no.2
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    • pp.197-209
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    • 2016
  • The Spacecraft (S/C) numerical sine test-predictions are usually performed through Finite Element Method (FEM) Frequency Response Analysis (FRA), that is the hypothesis of steady-state responses to harmonic excitation to the S/C base is made. In the test practice, the responses are transient and may be significantly different from those predicted through FRA. One of the most significant causes of discrepancy between prediction and test consists in the beating phenomena. After a brief overview of the topic, the typical causes of beating are described in the first part of the paper. Subsequently, focus is made on the sine sweep rate effect, which often leads to have beatings after the resonance of weakly damped modes. In this work, the approach illustrated in the literature for calculating the sine sweep rate effect in the case of Single-Degree-Of-Freedom (SDOF) oscillators is extended to Multi-Degrees-Of-Freedom (MDOF) systems, with the aim of increasing the accuracy of the numerical sine test-predictions. Assumptions and limitations of the proposed methodology are detailed along the paper. Several assessments with test results are discussed and commented.

Effects of Guaruhaebaekbanha-tang Extract on Beating Rate and LDH Activity in Cultured Rat Myocardial Cells (과루해백반하탕 추출물이 배양 심근세포의 박동수와 LDH 활성도에 미치는 영향)

  • An Hyo Chang;Kwon Kang Beam;Park Eun Young;Jang Seung Ho;Ryu Do Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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    • pp.289-295
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    • 2002
  • To certify the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity was measured using MTT, LDH activity and Beating rate assay in the presence of Guaruhaebaekbanha-tang(GHBT) extracts or single constituents of this prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present study, xanthine oxidase/hypoxanthine(XO/HX) resulted in a decrease in cell viability, increases in LDH activity in culture medium and decreases in beating rate in cultured myocardial cells. In the effect of GHBT extract, it showed the prevention from the XO/HX-induced cardiotoxicity by the increases of cell viability and beating rate as well as the decrease of LDH activity. In the protective effect of Fructus Trichosanthis(FT), Bulbus Allii Macrostemi(BAM) and Rhizoma Pinelliae(RP), all the extracts were significantly effective in the protection of XO/HX-induced cardiotoxocity in cultured myocardial cells by the increase of beating rate as well as th decrease of LDH activity. From these results, they show that XO/HX is cardiotoxic in cultured myocardial cells derived from neonatal rat, and it suggests that GHBT, FT, SAM, RP extracts are positively effective in the blocking in XO/HX-induced cardiotoxicity.

Effects of Fructus Schisandrae Water Extract on Cultured Mouse Myocardial Cells Induced by Xanthine Oxidase/Hypoxanthine (오미자 추출물이 산소지유기에 의하여 손상된 생쥐의 배양 심근세포에 미치는 영향)

  • 주은정
    • Journal of Nutrition and Health
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    • v.33 no.7
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    • pp.739-744
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    • 2000
  • The purpose of this study was to elucidate protective effect of Fructus Schsandrae(FS) water extract against xanthine oxidase/hypoxanthine(XO/HX)-induced cardiotoxicity in myocardial cells this experiment was performed. Cardiotoxicity of XO/HX was examined by MTT(MTT [3-(4,5-dimethylthiazol-2-yl)-2.5,-diphenyl tetrazolium bromide) assay. XO/HX induced the decrease of cell viability. Also XO/HX induced the increase of LDH activity and the decrease of beating rate on cultured myocardial cells in a dose-dependent manner. To investigate cardioprotective effect of FS water extract cultures were preincubated with FS water extract for 3 hours. Cultures were then exposed to XO/HX for 72 hours. FS water extract have an efficacy in decreaasing LDH activity and increasing heart beating rate on cultured myocardial cells damaged by XO/HX. From the results it is suggested that XO/HX may show toxic effect in cultured myocardial cells derived from neonatal mouse and FS water extract is effective in the prevention of XO/HX-induced cardiotoxicity.

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Effect of Beating Time and Fines Content on the Drainage Properties of BKP (고해처리와 미세분 함량에 따른 BKP의 탈수특성변화)

  • 성용주;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.1
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    • pp.52-60
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    • 1999
  • Drainage rate in wet-end, which has significant influences on the production capacity, product quality and process economics in papermaking, becomes an important factor in the modern high speed papermaking processes owing to increased level of fines contained in today's pulp materials and increased papermaking system closure. A study was carred out to investigate the influence of beating and fines content on natural and vacuum dewatering using a vacuum drainage tester. Increase in beating and accumulation of fines in the stock decreased natural dewatering, Vacuum dewatering effect, however, increased substantially as beating and fines content were increased. But this increase in vacuum dewatering decreased again when a stock is severely beaten or fines content is greater than 35%. Above this level of fines content, mobile fines migrates to the interstices of the forming web to cause sealing or plugging which restrict fluid movement through the web.

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All-optical Flip-flop based on Optical Beating and Bistability in an Injection-locked Fabry-Perot Laser Diode

  • Kim, Junsu;Lee, Hyuek Jae;Park, Chang-Soo
    • Journal of the Optical Society of Korea
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    • v.20 no.6
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    • pp.698-703
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    • 2016
  • We report a new all-optical flip-flop (AOFF) with a quite simple structure, using optical beating in an injection-locked Fabry-Perot laser diode (FP-LD) with optical bistability. While conventional AOFF methods using an injection-locked FP-LD require additional devices such as secondary FP-LDs or polarization controllers for reset operation, the proposed method can be implemented using only a single commercially available FP-LD with set and reset signals. The optical beating induces intensity fluctuations inside the FP-LD, and releases the locking state to the reset state. Even though we demonstrated the AOFF at 100 Mbit/s, we expect that its operation rate could extend to 10 Gbit/s, according to the limit of the FP-LD's frequency response.

Effects of Sujeom-san Water Extract in Cultured Rat Myocardial Cells (수념산 전탕액이 배양 심근세포에 미치는 영향)

  • Jean Young Seok;Kwon Kang Beam;Park Eun Young;Soong Eun Kyung;Park Seung Taeck;Ryu Do Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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    • pp.353-358
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    • 2002
  • To test the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity of xanthine oxidase/hypoxanthine (XO/HX) was examined using MTT, TBARS, and beating rate assay in the presence of water extract of Sujeom-san(SJS) or single consituents of its prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present paper, XO/HX resulted in a decrease in viability and beating rate and increases in lipid peroxidation in cultured myocardial cells. In the effect of SJS water extract, it showed effects from the cardiocytotoxicity induced by XO/HX treatment such as increases in beating rate and decreases in lipid peroxidation. In the effect of Rhizoma Corydalis (RC), Faeces Trogopterori (FT), Fructus Amomi Tsaoko (FAT) and Myrrha on the cardiocytotoxicity, they were significantly effective in blocking the XO/HX-induced cardiocytotoxicity by increase of beating rate in FAT and FT group as well as decrease of lipid peroxidation in FT and RC group. These results show that oxygen free radical elicits toxic effects in cultured myocardial cells derived from neonatal rat, and suggest that water extract of Sujeomsan, Rhizoma Corydalis, Faeces Trogopterori, Fructus Amomi Tsaoko or Myrrha is very effective in the prevention of xanthine oxidase/hypoxanthine- induced cardiotoxicity.

Effects of Tongryeong-san and Constituents Extract in Cultured Rat Myocardial Cells (통령산과 구성약물 추출물이 배양 심근세포에 미치는 영향)

  • Seong Eun Kyung;Kwon Kang Beom;Kim In Su;Kang Gil Seong;Kim In Gyu;Kim In Seob;Ryu Do Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.4
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    • pp.1031-1036
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    • 2003
  • To certify the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity was measured using TBARS assay and Beating rate in the presence of Tongryeong-san(TRS) extracts or single constituents of this prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present study, xanthine oxidase/hypoxanthine (XO/HX) resulted in a increase in lipid peroxidation and decreases in beating rate in cultured myocardial cells. In the effect of TRS extract, it showed the prevention from the XO/HX-induced cardiotoxicity by the increases of beating rate as well as the decrease of lipid peroxidation, In the protective effect of Faeces Trogopterori(FT), Pollen Typhae(PT), Caulis Akebiae(CA) and Radix Paeoniae Rubra(PRR), all the extracts were significantly effective in the protection of XO/HX-induced cardiotoxocity in cultured myocardial cells by the increase of beating rate as well as th decrease of lipid peroxidation. From these results, they show that XO/HX is cardiotoxic in cultured myocardial cells derived from neonatal rat, and it suggests that TRS, FT, PT, CA and PRR extracts are positively effective in the blocking in XO/HX-induced cardiotoxicity.

A study on the application and manufacture of paper sheet containing lyocell fiber( I ) (Lyocell 섬유를 함유한 종이의 제조 및 적용에 관한 연구( I ))

  • 김종열;류운형;유성종;김정열;신창호;김영호
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.1
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    • pp.99-106
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    • 2000
  • In order to investigate the applicability of lyocell fiber to filter paper, papper sheets were manufactured with the addition of lyocell fibers in various length(1.5 denier: 2, 3, 4mm) and content(10, 30, 50%) and their physical characters, such as fibrilation rate, adsorption efficiency of methylene blue(MB), paper formation, and crimping ability, etc, were tested. The level of main fibrilation from lyocell fiber was higher in wet beating process than that in free beating because of the higher strength of lyocell fiber compared with wood fiber. Fibrilation could be observed at the degree of beating over 30$^{\circ}$ SR in wet beating with Valley beater. The air permeability and tear factor of the paper increased and the paper formation index decreased according to the increase of fiber length. The weak binding force of lyocell fiber in spite of its higher fiber strength, might be a limitng factor in addition of lyocell fiber to the natural wood pulp in manufacturing the paper having the needed physical properties. High contents of wood pulp decreased air permeability, the breaking length, tear factor, the bursting strength, and paper formation index in paper sheets. As the contents of lyocell increased from 10% to 100%, the adsorption efficiency of MB was elevated to 1.7-7.9 times compared with that in 100% wood pulp. But the length of lyocell fiber did not affect the MB adsorption.

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